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  • 101.
    Laska, Matthias
    et al.
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi.
    Rosandher, Å.
    Hommen, S.
    Olfactory discrimination of aliphatic odorants at 1 ppm: Too easy for CD-1 mice to show odor structure-activity relationships?2008Ingår i: Journal of Comparative Physiology A. Sensory, neural, and behavioral physiology, ISSN 0340-7594, E-ISSN 1432-1351, Vol. 194, nr 11, s. 971-980Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Using an operant conditioning paradigm we tested the ability of CD-1 mice to discriminate between 25 odorants comprising members of five homologous series of aliphatic odorants (C4-C8) presented at a gas phase concentration of 1 ppm. We found (a) that all mice significantly discriminated between all 50 stimulus pairs that involved odorants sharing the same functional group, but differing in carbon chain length, as well as between all 50 stimulus pairs that involved odorants sharing the same carbon chain length but differing in functional group, (b) a significant negative correlation between discrimination performance and structural similarity of odorants in terms of differences in carbon chain length with the acetic esters and the 2-ketones, but not with the 1-alcohols, n-aldehydes, and n-carboxylic acids tested, and (c) that odorant pairs differing in functional group were significantly better discriminated than odorant pairs differing in carbon chain length. These findings demonstrate that CD-1 mice have excellent discrimination ability for structurally related aliphatic odorants, that correlations between discrimination performance and structural similarity of odorants are odorant class-specific rather than a general phenomenon, and that both carbon chain length and type of functional group play an important role for odor quality coding in mice. © 2008 Springer-Verlag.

  • 102.
    Laska, Matthias
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Rosandher, Åsa
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Hommen, Sara
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Olfactory Discrimination of Aliphatic Odorants at 1 PPM - Too Easy for Mice to Show Odor Structure-Activity Relationships?2008Ingår i: Chemical Senses, ISSN 0379-864X, E-ISSN 1464-3553, Vol. 33, nr 8, s. S158-S158Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    Functional studies suggest that the neural representations of odorants vary systematically as a function of molecular structural features such as carbon chain length or functional group. Psychophysical studies in both humans and animal models have reported some correlations between perceived odor quality and these molecular properties but the generality of such correlations is unknown.  Using an operant  conditioning  paradigm  we therefore  tested the ability of CD-1 mice to discriminate  between 25 odorants comprising members of five homologous  series of aliphatic odorants (C4-C8) presented at a gas phase concentration of 1 ppm. We found a) that all mice significantly discriminated  between all 50 stimulus pairs that  involved odorants sharing the same functional  group,  but differing in carbon  chain length, as well as between all 50 stimulus pairs that involved odorants sharing the same carbon chain length but differing in functional  group, b) a significant negative cor- relation between discrimination  performance and structural similarity of odorants in terms of differences in carbon chain length with the acetic esters and the 2-ketones, but not with the 1-alcohols, n-aldehydes,  and n-carbox- ylic acids tested, c) a lack of systematic differences in discrimination per- formance   as   a   function   of   type   of   functional   group,   and   d)   that presentation of stimuli at 0.1 ppm did not impair discrimination perform- ance. These findings demonstrate that CD-1 mice have an excellent discrim- ination   ability   for  structurally  related   aliphatic   odorants.  Given  that olfactory discrimination performance critically depends on stimulus concen- tration, it may be that presentation of odorants at 1 ppm was too easy (that is: too high above detection threshold)  for the mice to show consistent odorstructure-activity relationships.

  • 103.
    Laska, Matthias
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Svelander, M.
    Amundin, Mats
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Successful acquisition of an olfactory discrimination paradigm by South African fur seals, Arctocephalus pusillus2008Ingår i: Physiology and Behavior, ISSN 0031-9384, E-ISSN 1873-507X, Vol. 93, nr 4-5, s. 1033-1038Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The present study demonstrates that South African fur seals, Arctocephalus pusillus, can successfully be trained to discriminate between objects on the basis of odor cues. Using a task based on a food-rewarded two-choice discrimination of simultaneously presented odor stimuli the animals acquired the basic operant conditioning paradigm within 480 to 880 stimulus contacts. Moreover, the fur seals could readily transfer to new S+ and S- stimuli, were capable of distinguishing between fish- and non-fish odors as well as between two fish odors, and were able to remember the reward value of previously learned odor stimuli even after 2- and 15-week breaks. The precision and consistency of the fur seals' performance in tests of discrimination ability and memory demonstrate the suitability of this paradigm for assessing olfactory function in this pinniped. An across-species comparison of several measures of olfactory learning capabilities such as speed of initial task acquisition and ability to master transfer tasks shows that A. pusillus is similar in performance to non-human primates, but inferior to rodents such as mice and rats. The results support the assumption that fur seals may use olfactory cues for social communication and food selection and that the sense of smell may play an hitherto underestimated role in the control of their behavior. © 2008 Elsevier Inc. All rights reserved.

  • 104.
    Linander, Nellie
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska högskolan.
    Hemper de Ibarra, Natalie
    Center for Research in Animal Behaviour, University of Exeter, UK.
    Laska, Matthias
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Olfactory Detectability of L-Amino Acids in the European Honeybee (Apis mellifera)2012Ingår i: Chemical Senses, ISSN 0379-864X, E-ISSN 1464-3553, Vol. 37, nr 7, s. 631-638Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The honeybee is one of several insect model systems for the study of olfaction, yet our knowledge regarding the spectrum ofodorants detectable by Apis mellifera is limited. One class of odorants that has never been tested so far are the amino acids,which are important constituents of floral nectar. Using the proboscis extension response paradigm, we assessed whether theodor of amino acids is detectable for honeybees and determined olfactory detection thresholds for those amino acids that weredetectable. We found that honeybees are able to detect the odor of 5 of the 20 proteinogenic amino acids when presented ata concentration of 50 or 100 mM. Median olfactory detection thresholds for these 5 amino acids were 12.5 mM with L-tyrosineand L-cysteine, 50 mM with L-tryptophan and L-asparagine, and 100 mM with L-proline. All detection thresholds were muchhigher than reported concentrations of amino acids in floral nectars. We conclude that in the foraging and feeding context,honeybees are likely to detect amino acids through taste rather than olfaction. Across-species comparisons of the detectabilityof and sensitivity to amino acids suggest that the number of functional genes coding for olfactory receptors may affect botha species’ sensitivity for odorants and the breadth of its spectrum of detectable odorants.

  • 105. Beställ onlineKöp publikationen >>
    Lindgren, Isa
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Cardiovascular beta-adrenergic signaling: Maturation and programming effects of hypoxia in a chicken model2010Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Despite the importance of β-adrenergic receptors (βARs) in cardiovascular disease, not much is known about how prenatal hypoxia effects βAR signaling in the postnatal animal. Thus, the aim of this thesis was to characterize the pre- and postnatal maturation of the cardiovascular βARs and the effects of chronic prenatal hypoxia on βAR signaling in the embryo and adult animal using the chicken as experimental model.

    βARs belong to the seven-transmembrane receptor family of G-protein coupled receptors and are crucial for cardiovascular development, growth and regulation. In the cardiovascular system there are two dominant  subtypes, β1AR and β2AR, whose main ligands are the biogenic catecholamines epinephrine and norepinephrine. When stimulated, βARs primarily couple to the stimulatory G-protein (Gas) that stimulates adenylyl cyclase to convert ATP to cAMP. cAMP increases ino- and chronotropy of the heart and causes relaxation of blood vessels. β2ARs also have the ability to switch to inhibitory G-protein (Gi) signaling that decreases the cAMP production. To protect the cardiovascular system from overstimulation, the βARs desensitize and downregulate in the case of prolonged elevation of catecholamines. This blunts the cardiovascular response and the mechanisms behind desensitization/downregulation, including the β2AR switch to Gi signaling, are closely linked to cardiovascular disease and are of immense importance in medical therapeutics.

    Hypoxic stress releases catecholamines and thereby triggers βAR responses and desensitization/downregulation mechanisms. Hypoxia quite commonly occurs in utero and it is well known that prenatal insults, like malnutrition or hypoxia, are coupled to an increased risk of developing adult cardiovascular disease. This is referred to as developmental programming and constitutes an important and modern field of research.

    In this thesis, I show that; 1) the developmental trajectory for organ growth, especially the heart, is affected by hypoxia, 2) chronic prenatal hypoxia causes cardiac embryonic βAR sensitization, but causes desensitization postnatally suggesting that there is a hypoxia-induced “programming” effect on adult β-adrenoceptor function, 3) the adult βAR desensitization following prenatal hypoxia is linked to a decrease in β1AR/β2AR ratio, a decrease in cAMP following βAR stimulation with isoproterenol and an increase in Gas, 4) the chorioallantoic (CA) membrane arteries display hypoxic vasoconstriction, but lack 8-adrenergic reactivity and 5) hypotension of the chronically hypoxic chicken embryo is linked to a potent βAR relaxation of the CA vasculature and an increased AR sensitivity of the systemic arteries with no changes in heart rate.

    In conclusion, chronic prenatal hypoxia causes growth restriction, re-allocation and has programming effects on the βAR system in the adult. The latter indicates that the βAR system is an important factor in studying hypoxic developmental programming of adult cardiovascular disease.

    Delarbeten
    1. Sensitivity of organ growth to chronically low oxygen levels during incubation in Red Junglefowl and domesticated chicken breeds
    Öppna denna publikation i ny flik eller fönster >>Sensitivity of organ growth to chronically low oxygen levels during incubation in Red Junglefowl and domesticated chicken breeds
    2011 (Engelska)Ingår i: Poultry Science, ISSN 0032-5791, E-ISSN 1525-3171, Vol. 90, nr 1, s. 126-135Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Genetic selection programs have imposed large phenotypic changes in domesticated chicken breeds that are also apparent during embryonic development. Broilers, for example, have a faster growth rate before hatching in comparison with White Leghorns, indicating that the allocation of resources toward different functions already begins before hatching. Therefore, we hypothesized that embryonic organ growth would follow different developmental trajectories and would be differentially affected by an oxygen shortage during incubation. Heart, brain, and liver growth were studied in broiler, White Leghorn, and Red Junglefowl embryos at embryonic (E) ages E11, E13, E15, E18, and E20, and the results were fitted to growth allometric equations to determine the degree of organ stunting or sparing caused by low oxygen during incubation. Hypoxia caused a 3-fold larger mortality in Red Junglefowl than in the domesticated breeds, with a similar impairment of embryonic growth of 18%, coupled with a reduction in yolk utilization of 56%. Relative brain size was not affected by hypoxia in any breed, but a substantial stunting effect was observed for the liver and heart at late embryonic ages, with marked differences between breeds. In Red Junglefowl, only the heart was stunted. In White Leghorns, only the liver was stunted, and in broilers, both organs were stunted. These results can be explained in terms of the selection pressure on long-term production traits (reproductive effort) in White Leghorns, requiring a more efficient lipid metabolism, compared with the selection pressure on shorter-term production traits (growth) in broilers, requiring overall metabolic turnover and convective nutrient delivery to all tissues. At the same time, a remarkable sparing of the heart was observed in broilers and Red Junglefowl between E11 and E15, which suggests that cardiac growth can be manipulated during embryonic development. This result could be relevant for manipulating the phenotype of the heart for management purposes at a developmental stage when the bird is most versatile and phenotypically malleable.

    Ort, förlag, år, upplaga, sidor
    Poultry Science Association, 2011
    Nyckelord
    broiler, domestication, organ growth, hypoxia, cardiovascular development
    Nationell ämneskategori
    Teknik och teknologier
    Identifikatorer
    urn:nbn:se:liu:diva-64572 (URN)10.3382/ps.2010-00996 (DOI)000285504700016 ()
    Tillgänglig från: 2011-01-28 Skapad: 2011-01-28 Senast uppdaterad: 2017-12-11
    2. Chronic prenatal hypoxia sensitizes beta-adrenoceptors in the embryonic heart but causes postnatal desensitization
    Öppna denna publikation i ny flik eller fönster >>Chronic prenatal hypoxia sensitizes beta-adrenoceptors in the embryonic heart but causes postnatal desensitization
    2009 (Engelska)Ingår i: AMERICAN JOURNAL OF PHYSIOLOGY-REGULATORY INTEGRATIVE AND COMPARATIVE PHYSIOLOGY, ISSN 0363-6119, Vol. 297, nr 2, s. R258-R264Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Prenatal hypoxia in mammals causes fetal growth restriction and catecholaminergic overstimulation that, in turn, alter signaling pathways associated with adrenergic receptors. beta-Adrenoceptors (beta-ARs) are essential for fetal cardiac development and regulation of cardiac contractility. We studied the effects of chronic prenatal hypoxia on cardiac beta-AR signaling and the incidence of alterations in the juvenile beta-AR system due to the embryonic treatment. We measured functional beta-AR density (B-max) through binding with [H-3]CGP-12177 and the effect of agonists on beta-AR-dependent contractility (pEC(50)) through concentration-response curves to epinephrine. Eggs from broiler chickens were incubated in normoxia (N, 21% O-2) or chronic hypoxia (H, 14% O-2). Cardiac tissue from embryos and juveniles was used (15 and 19 day of embryonic development and 14 and 35 days posthatching, E19, E15, P14, and P35, respectively). Relative cardiac enlargement was found in the hypoxic groups at E15, E19, and P14, but not P35. B-max significantly decreased in E19H. Bmax more than doubled posthatching but decreased from P14 to P35. The sensitivity to epinephrine was lower in E19N compared with E15N, but hypoxia increased the sensitivity to agonist in both E15H and E19H. Despite maintained receptor density, the P35H juvenile displayed a decreased sensitivity to beta-AR agonist, something that was not seen in P14H. The postnatal decrease in beta-AR sensitivity as an effect of chronic prenatal hypoxia, without a concomitant change in beta-AR density, leads us to conclude that the embryonic hypoxic challenge alters the future progression of beta-AR signaling and may have important implications for cardiovascular function in the adult.

    Nyckelord
    beta-adrenergic; embryonic development; hypoxia; receptor density; receptor sensitivity
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-20149 (URN)10.1152/ajpregu.00167.2009 (DOI)
    Tillgänglig från: 2009-09-01 Skapad: 2009-08-31 Senast uppdaterad: 2011-02-04Bibliografiskt granskad
    3. Postnatal β-adrenergic desensitization caused by chronic prenatal hypoxia is linked to anincrease in Gas and decreased β1AR/β2AR ratio
    Öppna denna publikation i ny flik eller fönster >>Postnatal β-adrenergic desensitization caused by chronic prenatal hypoxia is linked to anincrease in Gas and decreased β1AR/β2AR ratio
    (Engelska)Manuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Prenatal hypoxia leads to growth restriction and increased risk of adult cardiovascular disease. We have previously demonstrated that prenatal hypoxia desensitizes the 5 week chicken heart, but has no effect in the 2 week heart. This indicates that there is a programming effect of prenatal hypoxia on βAR signaling. It has been shown in a rat model that the β1AR/β2AR ratio and increased Gai expression is related to decreased βAR sensitivity measured by cAMP production after βAR stimulation. Thus, the aim of this study was to determine whether the observed decrease in βAR sensitivity in the prenatally hypoxic 5 week chicken heart is linked to changes in β1AR/β2AR ratio and Gai expression and what effects it has on the cAMP accumulation due to βAR stimulation.

    We incubated eggs in normoxia (N, 20.95% O2) or hypoxia from day 0 (H, 14% O2) and raised the post-hatchlings to 5 weeks of age in normoxic conditions. The hearts were sampled and the β1AR/β2AR ratio in intact heart slices was assessed through competitive binding of [3H]CGP-12177 with specific β1AR or β2AR blockers (CGP-20712A and ICI-118,551 respectively). Gas and Gai expression was assessed by Western blot and an immunoassay was used to determine the cAMP accumulation after βAR stimulation with isoproterenol. We found that there is indeed a decrease in β1AR/β2AR ratio. Surprisingly, Gas increased in prenatally hypoxic hearts and not Gai as hypothesized. cAMP levels after isoproterenol stimulation of βARs was lower in H than in N.

    In conclusion, the desensitization of βARs to epinephrine in 5 week chickens exposed to prenatal hypoxia was confirmed by significantly lower cAMP production in response to βAR stimulation compared to the controls. Furthermore, the β1AR/β2AR ratio in prenatally hypoxic animals was decreased similarly to the β1AR/β2AR ratio change seen in heart failure. Gas expression was increased, but again considering the lower cAMP accumulation in response to βAR stimulation, the increased Gas seems to be inactive. We speculate that the 5 week chicken exposed to prenatal hypoxia might be displaying early signs of heart failure.

    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-65357 (URN)
    Tillgänglig från: 2011-02-04 Skapad: 2011-02-04 Senast uppdaterad: 2011-02-04
    4. Reactivity of chicken chorioallantoic arteries, avian homologue of human fetoplacental arteries
    Öppna denna publikation i ny flik eller fönster >>Reactivity of chicken chorioallantoic arteries, avian homologue of human fetoplacental arteries
    2010 (Engelska)Ingår i: Journal of Physiology and Pharmacology, ISSN 0867-5910, E-ISSN 1899-1505, Vol. 61, nr 5, s. 619-628Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    The reactivity of human fetoplacental arteries is regulated by humoral and local factors of maternal and fetal origin. The chorioallantoic (CA) arteries of bird embryos are homologous to fetoplacental arteries and fulfill the same gas-exchange purpose without maternal influences, but their reactivity has not been studied in detail. In the present study we hypothesized that CA arteries would respond to vasoactive factors similarly to fetoplacental arteries and the response would change during development between maximal vascular CA expansion (15 of the 21 days incubation period) and prior to hatching. Therefore, we analyzed the reactivity of third order arteries (similar to 200 mu m) from the CA membrane of 15 and 19 day chicken embryos. CA arteries contracted in response to K+, the thromboxane A(2) mimetic U46619, endothelin-1, acetylcholine and acute hypoxia, but showed no reaction to alpha-adrenergic stimulation (phenylephrine). The nitric oxide donor sodium nitroprusside, the adenylyl cyclase agonist forskolin, and the beta-adrenergic agonist isoproterenol relaxed CA arteries precontracted with K+ or U46619. The contraction evoked by acetylcholine and the relaxations evoked by sodium nitroprusside and isoproterenol decreased with incubation age. In conclusion, CA arteries share many characteristics with human fetoplacental arteries, such as pronounced relaxation to beta-adrenergic stimuli and hypoxic vasoconstriction. Our study will be the foundation for future studies to explain disparate and common responses of the CA and fetoplacental vasculature.

    Ort, förlag, år, upplaga, sidor
    Polish Physiological Society, 2010
    Nyckelord
    beta-adrenergic agonist, chicken embryo, chorioallantoic membrane, hypoxic vasoconstriction, thromboxane A(2), vasoreactivity
    Nationell ämneskategori
    Teknik och teknologier
    Identifikatorer
    urn:nbn:se:liu:diva-63392 (URN)000284790500013 ()
    Tillgänglig från: 2010-12-17 Skapad: 2010-12-17 Senast uppdaterad: 2017-12-11
    5. Hypotension in the chronically hypoxic chicken embryo is related to the β-adrenergic response of chorioallantoic and femoral arteries and not to bradycardia
    Öppna denna publikation i ny flik eller fönster >>Hypotension in the chronically hypoxic chicken embryo is related to the β-adrenergic response of chorioallantoic and femoral arteries and not to bradycardia
    2011 (Engelska)Ingår i: American Journal of Physiology. Regulatory Integrative and Comparative Physiology, ISSN 0363-6119, E-ISSN 1522-1490, Vol. 301, nr 4, s. R1161-R1168Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Prolonged fetal hypoxia leads to growth restriction and can cause detrimental pre- and postnatal alterations. The embryonic chicken is a valuable model to study such effects of prenatal hypoxia, but little is known about long-term hypoxic effects on cardiovascular regulation in the chicken embryo. We investigated heart rate and blood pressure responses to chronic prenatal hypoxia in the chicken embryo (19 days) and hypothesized that it would exhibit hypotension due to bradycardia and βAR-mediated relaxation of the systemic (femoral) and/or the chorioallantoic (CA) arteries. We first measured heart rate (HR) and blood pressure (BP) in 19 day embryos incubated from day 0 in normoxia or hypoxia (14-15% O2). Secondly, we studied β-adrenoceptor (βAR)-mediated contraction, relaxation to the β-adrenoceptor (βAR) agonist isoproterenol and relaxation to forskolin in femoral and CA arteries using wire myography techniques. Chronic hypoxia caused a close to significant hypotension compared to the controls (Mean arterial pressure 3.19±0.18 vs. 2.59±0.13 kPa, normoxia vs. hypoxia respectively, P=0.056), but not bradycardia. All vessels relaxed in response to βAR stimulation with isoproterenol, but the CAM arteries completely lacked an βAR response. Furthermore, hypoxia increased the sensitivity of femoral (but not CA arteries) to isoproterenol. Hypoxia also increased the responsiveness of femoral arteries to the adenylate cyclase activator forskolin. In conclusion, hypotension in chronically hypoxic chicken embryos is more likely the consequence of elevated levels of circulating catecholamines acting on vascular beds with exclusive (CA arteries) or exacerbated (femoral arteries) βAR-mediated relaxation, rather than a consequence of bradycardia.

    Ort, förlag, år, upplaga, sidor
    American Physiological Society, 2011
    Nyckelord
    Prenatal hypoxia, hypoxic hypotension, chorioallantoic membrane, β-adrenoceptors, α-adrenoceptors
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-65359 (URN)10.1152/ajpregu.00458.2010 (DOI)000295881600031 ()
    Anmärkning
    Funding agencies|FORMAS, the Swedish Research Council for Environment||Agricultural Sciences and Spatial Planning||Wallenberg Foundation||Tillgänglig från: 2011-02-04 Skapad: 2011-02-04 Senast uppdaterad: 2017-12-11
    Ladda ner fulltext (pdf)
    Cardiovascular beta-adrenergic signaling: Maturation and programming effects of hypoxia in a chicken model
    Ladda ner (pdf)
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  • 106.
    Lindgren, Isa
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Altimiras, Jordi
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Chronic prenatal hypoxia sensitizes beta-adrenoceptors in the embryonic heart but causes postnatal desensitization2009Ingår i: AMERICAN JOURNAL OF PHYSIOLOGY-REGULATORY INTEGRATIVE AND COMPARATIVE PHYSIOLOGY, ISSN 0363-6119, Vol. 297, nr 2, s. R258-R264Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Prenatal hypoxia in mammals causes fetal growth restriction and catecholaminergic overstimulation that, in turn, alter signaling pathways associated with adrenergic receptors. beta-Adrenoceptors (beta-ARs) are essential for fetal cardiac development and regulation of cardiac contractility. We studied the effects of chronic prenatal hypoxia on cardiac beta-AR signaling and the incidence of alterations in the juvenile beta-AR system due to the embryonic treatment. We measured functional beta-AR density (B-max) through binding with [H-3]CGP-12177 and the effect of agonists on beta-AR-dependent contractility (pEC(50)) through concentration-response curves to epinephrine. Eggs from broiler chickens were incubated in normoxia (N, 21% O-2) or chronic hypoxia (H, 14% O-2). Cardiac tissue from embryos and juveniles was used (15 and 19 day of embryonic development and 14 and 35 days posthatching, E19, E15, P14, and P35, respectively). Relative cardiac enlargement was found in the hypoxic groups at E15, E19, and P14, but not P35. B-max significantly decreased in E19H. Bmax more than doubled posthatching but decreased from P14 to P35. The sensitivity to epinephrine was lower in E19N compared with E15N, but hypoxia increased the sensitivity to agonist in both E15H and E19H. Despite maintained receptor density, the P35H juvenile displayed a decreased sensitivity to beta-AR agonist, something that was not seen in P14H. The postnatal decrease in beta-AR sensitivity as an effect of chronic prenatal hypoxia, without a concomitant change in beta-AR density, leads us to conclude that the embryonic hypoxic challenge alters the future progression of beta-AR signaling and may have important implications for cardiovascular function in the adult.

  • 107.
    Lindgren, Isa
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Altimiras, Jordi
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Sensitivity of organ growth to chronically low oxygen levels during incubation in Red Junglefowl and domesticated chicken breeds2011Ingår i: Poultry Science, ISSN 0032-5791, E-ISSN 1525-3171, Vol. 90, nr 1, s. 126-135Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Genetic selection programs have imposed large phenotypic changes in domesticated chicken breeds that are also apparent during embryonic development. Broilers, for example, have a faster growth rate before hatching in comparison with White Leghorns, indicating that the allocation of resources toward different functions already begins before hatching. Therefore, we hypothesized that embryonic organ growth would follow different developmental trajectories and would be differentially affected by an oxygen shortage during incubation. Heart, brain, and liver growth were studied in broiler, White Leghorn, and Red Junglefowl embryos at embryonic (E) ages E11, E13, E15, E18, and E20, and the results were fitted to growth allometric equations to determine the degree of organ stunting or sparing caused by low oxygen during incubation. Hypoxia caused a 3-fold larger mortality in Red Junglefowl than in the domesticated breeds, with a similar impairment of embryonic growth of 18%, coupled with a reduction in yolk utilization of 56%. Relative brain size was not affected by hypoxia in any breed, but a substantial stunting effect was observed for the liver and heart at late embryonic ages, with marked differences between breeds. In Red Junglefowl, only the heart was stunted. In White Leghorns, only the liver was stunted, and in broilers, both organs were stunted. These results can be explained in terms of the selection pressure on long-term production traits (reproductive effort) in White Leghorns, requiring a more efficient lipid metabolism, compared with the selection pressure on shorter-term production traits (growth) in broilers, requiring overall metabolic turnover and convective nutrient delivery to all tissues. At the same time, a remarkable sparing of the heart was observed in broilers and Red Junglefowl between E11 and E15, which suggests that cardiac growth can be manipulated during embryonic development. This result could be relevant for manipulating the phenotype of the heart for management purposes at a developmental stage when the bird is most versatile and phenotypically malleable.

  • 108.
    Lindgren, Isa
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska högskolan.
    Altimitas, Jordi
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Prenatal hypoxia programs changes in β-adrenergic signaling and postnatal cardiac contractile dysfunction2013Ingår i: American Journal of Physiology. Regulatory Integrative and Comparative Physiology, ISSN 0363-6119, E-ISSN 1522-1490, Vol. 305, s. R1093-R1101Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Prenatal hypoxia leads to an increased risk of adult cardiovascular disease. We have previously demonstrated a programming effect of prenatal hypoxia on the cardiac β-adrenergic (βAR) response. The aim of this study was to determine 1) whether the decrease in βAR sensitivity in prenatally hypoxic 5-wk old chicken hearts is linked to changes in β1AR/β2ARs, Gαi expression and cAMP accumulation and 2) whether prenatal hypoxia has an effect on heart function in vivo. We incubated eggs in normoxia (N, 21% O2) or hypoxia from day 0 (H, 14% O2) and raised the posthatchlings to 5 wk of age. Cardiac β1AR/β2ARs were assessed through competitive binding of [3H]CGP-12177 with specific β1AR or β2AR blockers. Gαs and Gαi proteins were assessed by Western blot and cAMP accumulation by ELISA. Echocardiograms were recorded in anesthetized birds to evaluate diastolic/systolic diameter and heart rate and tissue sections were stained for collagen. We found an increase in relative heart mass, β1ARs, and Gαs in prenatally hypoxic hearts. cAMP levels after isoproterenol stimulation and collagen content was not changed in H compared with N, but in vivo echocardiograms showed systolic contractile dysfunction. The changes in βAR and G protein subtypes may be indicative of an early compensatory stage in the progression of cardiac dysfunction, further supported by the cardiac hypertrophy and systolic contractile dysfunction. We suggest that it is not the changes in the proximal part of the βAR system that causes the decreased cardiac contractility, but Ca2+ handling mechanisms further downstream in the βAR signaling cascade.

  • 109.
    Lindgren, Isa
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Crossley II, Dane
    Biology Department, University of North Dakota, USA.
    Villamor, Eduardo
    Department of Pediatrics, GROW School for Oncology and Developmental Biology, Maastricht University Medical Center (MUMC+), The Netherlands.
    Altimiras, Jordi
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Hypotension in the chronically hypoxic chicken embryo is related to the β-adrenergic response of chorioallantoic and femoral arteries and not to bradycardia2011Ingår i: American Journal of Physiology. Regulatory Integrative and Comparative Physiology, ISSN 0363-6119, E-ISSN 1522-1490, Vol. 301, nr 4, s. R1161-R1168Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Prolonged fetal hypoxia leads to growth restriction and can cause detrimental pre- and postnatal alterations. The embryonic chicken is a valuable model to study such effects of prenatal hypoxia, but little is known about long-term hypoxic effects on cardiovascular regulation in the chicken embryo. We investigated heart rate and blood pressure responses to chronic prenatal hypoxia in the chicken embryo (19 days) and hypothesized that it would exhibit hypotension due to bradycardia and βAR-mediated relaxation of the systemic (femoral) and/or the chorioallantoic (CA) arteries. We first measured heart rate (HR) and blood pressure (BP) in 19 day embryos incubated from day 0 in normoxia or hypoxia (14-15% O2). Secondly, we studied β-adrenoceptor (βAR)-mediated contraction, relaxation to the β-adrenoceptor (βAR) agonist isoproterenol and relaxation to forskolin in femoral and CA arteries using wire myography techniques. Chronic hypoxia caused a close to significant hypotension compared to the controls (Mean arterial pressure 3.19±0.18 vs. 2.59±0.13 kPa, normoxia vs. hypoxia respectively, P=0.056), but not bradycardia. All vessels relaxed in response to βAR stimulation with isoproterenol, but the CAM arteries completely lacked an βAR response. Furthermore, hypoxia increased the sensitivity of femoral (but not CA arteries) to isoproterenol. Hypoxia also increased the responsiveness of femoral arteries to the adenylate cyclase activator forskolin. In conclusion, hypotension in chronically hypoxic chicken embryos is more likely the consequence of elevated levels of circulating catecholamines acting on vascular beds with exclusive (CA arteries) or exacerbated (femoral arteries) βAR-mediated relaxation, rather than a consequence of bradycardia.

  • 110.
    Lindgren, Isa
    et al.
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi.
    Zoer, B
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Villamor, E
    n/a.
    Reactivity of chicken chorioallantoic arteries, avian homologue of human fetoplacental arteries2010Ingår i: Journal of Physiology and Pharmacology, ISSN 0867-5910, E-ISSN 1899-1505, Vol. 61, nr 5, s. 619-628Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The reactivity of human fetoplacental arteries is regulated by humoral and local factors of maternal and fetal origin. The chorioallantoic (CA) arteries of bird embryos are homologous to fetoplacental arteries and fulfill the same gas-exchange purpose without maternal influences, but their reactivity has not been studied in detail. In the present study we hypothesized that CA arteries would respond to vasoactive factors similarly to fetoplacental arteries and the response would change during development between maximal vascular CA expansion (15 of the 21 days incubation period) and prior to hatching. Therefore, we analyzed the reactivity of third order arteries (similar to 200 mu m) from the CA membrane of 15 and 19 day chicken embryos. CA arteries contracted in response to K+, the thromboxane A(2) mimetic U46619, endothelin-1, acetylcholine and acute hypoxia, but showed no reaction to alpha-adrenergic stimulation (phenylephrine). The nitric oxide donor sodium nitroprusside, the adenylyl cyclase agonist forskolin, and the beta-adrenergic agonist isoproterenol relaxed CA arteries precontracted with K+ or U46619. The contraction evoked by acetylcholine and the relaxations evoked by sodium nitroprusside and isoproterenol decreased with incubation age. In conclusion, CA arteries share many characteristics with human fetoplacental arteries, such as pronounced relaxation to beta-adrenergic stimuli and hypoxic vasoconstriction. Our study will be the foundation for future studies to explain disparate and common responses of the CA and fetoplacental vasculature.

  • 111.
    Lindholm, Caroline
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Calais, A
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Jönsson, J
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Yngwe, N.
    SweHatch AB, 247 47 Flyinge, Sweden.
    Berndtson, E.
    SweHatch AB, 247 47 Flyinge, Sweden.
    Hult, E.
    SweHatch AB, 247 47 Flyinge, Sweden.
    Altimiras, Jordi
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska fakulteten.
    Slow and steady wins the race? No signs of reduced welfare in smallerbroiler breeder hens at four weeks of age2015Ingår i: Animal Welfare, ISSN 0962-7286, Vol. 24, nr 4, s. 447-454Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Broiler breeder chickens are commonly reared under strict feed-restriction regimes to reduce obesity-induced health and fertilityproblems during adult life, and are assumed to experience a reduced welfare due to the resulting hunger. In these conditions, feedcompetition could influence the growth rate, so that the individuals falling behind in growth would experience more stress and hunger.We hypothesised that these chickens are poor competitors due to a reactive coping style and experience a further reduced welfaresituation before size-sorting (‘grading’) at four weeks of age. Our results from open field, tonic immobility and home pen activity monitoringshow signs of lower fear and higher home-pen activity levels in smaller hens and do not support the idea of reactive coping.H/L ratios of smaller hens were also found to be lower, indicating less stress in these birds. Dissections of smaller and larger fourweekbreeder hens may offer an explanation in the form of a relatively larger gastrointestinal tract in smaller birds. We argue thatthis is a form of habituation to restricted feeding, offering these birds a physiological stress coping mechanism, and that low earlygrowth rate may not always be a sign of poorer welfare in broiler breeders.

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  • 112.
    Lindqvist, CES
    et al.
    Swedish Univ Agr Sci, Dept Anim Environm & Hlth, Sect Ethol, S-75007 Uppsala, Sweden.
    Schutz, KE
    Swedish Univ Agr Sci, Dept Anim Environm & Hlth, Sect Ethol, S-75007 Uppsala, Sweden.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Red jungle fowl have more contrafreeloading than white leghorn layers: Effect of food deprivation and consequences for information gain2002Ingår i: Behaviour, ISSN 0005-7959, E-ISSN 1568-539X, Vol. 139, s. 1195-1209Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Contrafreeloading (CFL), i.e. choosing food which requires work over free food, occurs at a higher rate in red jungle fowl (Gallus gallus) compared to White Leghorn layers. We examined whether this difference between breeds was altered by food deprivation and whether it affected the information gained about alternative food sources. In a first experiment, twenty birds of each breed were deprived for zero, three and six hours and then allowed a choice of feeding from freely available food or food mixed with wood shavings. In both breeds, CFL tended to decrease after deprivation, but jungle fowl consistently showed more CFL than Leghorns also after food deprivation. This shows that differences in CFL between breeds were not altered by food deprivation, and the larger CFL in jungle fowl may represent a genetically based difference in feeding strategy. In a second experiment, we examined whether the differences in CFL affected how the birds acquired information about alternative food sites of different quality. Twenty birds of each breed were allowed to forage during three 10 min sessions in a four armed maze, where symbols in each end of the arms indicated the location of four different quality food sources, 'high gain' (freely available food), 'medium gain' (70% food, 30% wood shavings), 'low gain' (30% food), and 'no gain' (100% wood shavings). Each bird was then tested in the same maze when the 'high gain' food source and its symbol had been removed, and the other three sources contained only the symbols and wood shavings. Jungle fowl chose the symbol indicating the best available food source significantly more often than the Leghorns. The results indicate that Leghorn gain less information during foraging, which may have consequences for their adaptation capacity in a production environment. This could either be a consequence of Leghorns showing less CFL, or a generally impaired learning capacity of Leghorns compared to jungle fowl.

  • 113. Beställ onlineKöp publikationen >>
    Lindqvist, Christina
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Domestication effects on foraging behaviour: consequences for adaptability in chickens2008Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The main aim of this thesis was to study domestication effects on foraging behaviour in chickens and to investigate whether and how domestication and selection for high production have influenced adaptability in chickens. Two domestic strains of chickens (egg layers and meat type chickens) and their wild ancestor, the red jungle fowl (RJF) were compared in different test situations with respect to foraging behaviour and adaptability. The domestic strains showed a modified foraging strategy, where they were less inclined to explore and feed from a hidden food source, i.e. they showed less contrafreeloading (CFL, the behaviour of working for food even though identical food can be easily obtained) than RJF. The difference in CFL between RJF and the layers were not altered by food deprivation, which suggests that the lower CFL in the layers represents a genetically based difference in feeding strategy. In addition, CFL decreased with age in RJF and layers and social isolation decreased CFL in RJF. Furthermore, when foraging, RJF acquired information about the quality of different food sources, which was utilised after a change in environmental conditions. Contrary to this, layers gained less information during foraging and showed an impaired spatial learning ability compared to RJF, and in this respect, layers showed a lower degree of adaptability. Chronic stress impaired the learning capacity of both breeds but RJF seemed to be overall faster to learn to locate food in a spatial learning task. Furthermore, stressed RJF started to eat faster in the spatial learning test than non-stressed RJF, and contrary to this, stressed layers showed a more passive response by prolonging the time to start feeding compared to non-stressed layers. This indicates a more active response to stress in RJF than in layers. Similarly, when RJF and layers were exposed to food deprivation, RJF showed an active response by increasing their time spent on foraging behaviour. The general results in this thesis most likely reflect different adaptive strategies, where RJF appear to be better adapted to a stochastic environment, and the domestic strains to grow and produce egg in a more predictable environment. The findings are in accordance with the resource allocation theory, which suggests that animals selected for high production are expected to reallocate a high proportion of resources into production traits and hence fewer resources might be left to other biological processes, e.g. exploratory behaviour. Selection for high production seems to influence the ability of chickens to cope with a changing environment, which may have implications for the welfare of chickens in a production environment.

    Delarbeten
    1. Red jungle fowl have more contrafreeloading than white leghorn layers: Effect of food deprivation and consequences for information gain
    Öppna denna publikation i ny flik eller fönster >>Red jungle fowl have more contrafreeloading than white leghorn layers: Effect of food deprivation and consequences for information gain
    2002 (Engelska)Ingår i: Behaviour, ISSN 0005-7959, E-ISSN 1568-539X, Vol. 139, s. 1195-1209Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Contrafreeloading (CFL), i.e. choosing food which requires work over free food, occurs at a higher rate in red jungle fowl (Gallus gallus) compared to White Leghorn layers. We examined whether this difference between breeds was altered by food deprivation and whether it affected the information gained about alternative food sources. In a first experiment, twenty birds of each breed were deprived for zero, three and six hours and then allowed a choice of feeding from freely available food or food mixed with wood shavings. In both breeds, CFL tended to decrease after deprivation, but jungle fowl consistently showed more CFL than Leghorns also after food deprivation. This shows that differences in CFL between breeds were not altered by food deprivation, and the larger CFL in jungle fowl may represent a genetically based difference in feeding strategy. In a second experiment, we examined whether the differences in CFL affected how the birds acquired information about alternative food sites of different quality. Twenty birds of each breed were allowed to forage during three 10 min sessions in a four armed maze, where symbols in each end of the arms indicated the location of four different quality food sources, 'high gain' (freely available food), 'medium gain' (70% food, 30% wood shavings), 'low gain' (30% food), and 'no gain' (100% wood shavings). Each bird was then tested in the same maze when the 'high gain' food source and its symbol had been removed, and the other three sources contained only the symbols and wood shavings. Jungle fowl chose the symbol indicating the best available food source significantly more often than the Leghorns. The results indicate that Leghorn gain less information during foraging, which may have consequences for their adaptation capacity in a production environment. This could either be a consequence of Leghorns showing less CFL, or a generally impaired learning capacity of Leghorns compared to jungle fowl.

    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-48342 (URN)10.1163/15685390260437335 (DOI)
    Tillgänglig från: 2009-10-11 Skapad: 2009-10-11 Senast uppdaterad: 2017-12-12
    2. Effects of age, sex and social isolation on contrafreeloading in red junglefowl (Gallus gallus) and White Leghorn fowl
    Öppna denna publikation i ny flik eller fönster >>Effects of age, sex and social isolation on contrafreeloading in red junglefowl (Gallus gallus) and White Leghorn fowl
    2008 (Engelska)Ingår i: Applied Animal Behaviour Science, ISSN 0168-1591, E-ISSN 1872-9045, Vol. 114, nr 3-4, s. 419-428Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Contrafreeloading (CFL), i.e. choosing to work to obtain food over free food, has been studied in many different species. White Leghorn laying hens selected for high production have a lower extent of CFL compared to their wild ancestor, red junglefowl. We studied the effects of age, sex and social isolation. on the extent of CFL in red junglefowl and White Leghorn layers.

    For 48 h, 30 birds of each breed were allowed a choice, between freely available food and food mixed with wood shavings. Both females and males were tested individually as young birds (8-10 weeks old) and when they were sexually mature (27-29 weeks old). To test the possible effects of social isolation, the same birds were also tested in pairs at 30 weeks of age.

    Junglefowl showed a higher extent of CFL at the younger age compared to Leghorns (33.7% vs. 22.7%: P = 0.05) and both breeds showed higher extent of CFL at a young age than when sexually mature (P < 0.001). There were no significant differences between the two breeds when they were sexually mature and tested individually but, when tested in pairs, junglefowl showed higher extent of CFL than Leghorns (31.7% vs. 17.0%; P < 0.001). There were no differences in the extent of CFL between the sexes in either breed.

    The results indicate that age and social isolation influence the extent of CFL in fowl. Furthermore, the results support earlier findings that the extent of CFL is lower in Leghorns than junglefowl, indicating a possible side-effect of selection for increased production.

    Nyckelord
    Domestication, Contrafreeloading, Junglefowl, White Leghorn, Age, Social isolation
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-16127 (URN)10.1016/j.applanim.2008.03.002 (DOI)
    Tillgänglig från: 2009-01-08 Skapad: 2009-01-07 Senast uppdaterad: 2017-12-14Bibliografiskt granskad
    3. A note on contrafreeloading in broilers compared to layer chicks
    Öppna denna publikation i ny flik eller fönster >>A note on contrafreeloading in broilers compared to layer chicks
    2006 (Engelska)Ingår i: Applied Animal Behaviour Science, ISSN 0168-1591, Vol. 101, nr 1-2, s. 161-166Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Contrafreeloading (CFL) is the behaviour where an animal chooses to work for food even when identical food can be obtained without any effort. Previous studies have suggested that the difference in CFL between White Leghorn layers and jungle fowl may be a side effect of selection for increased production traits in the Leghorn strain.

    In this experiment we studied to what extent broilers chicks (Cobb/Ross), which are highly selected for fast growth, perform CFL and compared this with a layer strain (Calder Ranger), which grows considerably slower. We predicted that broilers should have a lower degree of CFL compared to the layer strain, as an energy-saving response to the demands of rapid growth.

    During 48 h 10 pairs of each breed were given a choice between freely available food and food mixed with wood shavings. Behavioural observations were made twice each day. Broilers showed less CFL (p < 0.05), were more inactive (p < 0.001) and performed less active behaviours (p < 0.05) than layers.

    Our results support previous findings that decreased CFL in domestic fowl may indicate adaptive reallocation of energy resources in response to selection for increased production traits.

    Nyckelord
    Contrafreeloading; Resource allocation; Broiler; Laying hen
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-13000 (URN)10.1016/j.applanim.2006.01.006 (DOI)
    Tillgänglig från: 2008-03-11 Skapad: 2008-03-11
    4. Domestication and stress effects on contrafreeloading and spatial learning performance in red jungle fowl (Gallus gallus) and White Leghorn layers
    Öppna denna publikation i ny flik eller fönster >>Domestication and stress effects on contrafreeloading and spatial learning performance in red jungle fowl (Gallus gallus) and White Leghorn layers
    2009 (Engelska)Ingår i: BEHAVIOURAL PROCESSES, ISSN 0376-6357 , Vol. 81, nr 1, s. 80-84Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    White Leghorn layers (WL) show modified foraging strategies. compared to their ancestor, the red jungle fowl (RJF). Birds selected for high production may invest more resources into production traits and less in other biological Processes. This may affect the capacity to adapt to new or variable environments.

    Thirty birds of each of RJF and WL were raised in a stressful environment (unpredictable light:dark schedule) and 30 control animals of each breed in similar pens, but on a 12:12 h light:dark schedule. We studied the differences between breed and treatment with respect to contrafreeloading (CFL), spatial learning ability and the birds behaviour in a T-maze.

    WL showed less CFL, were less cautious in the test arena and showed an impaired spatial learning ability Compared with RJF in both test situations. Stress impaired spatial learning in both breeds, but stressed RJF showed a more active response to the test situation than non-stressed RJF, by starting to eat faster, while stressed WL prolonged their time to start eating compared to non-stressed WL. Our results may reflect different adaptive Strategies, where RJF appear better adapted to an unpredictable environment.

    Nyckelord
    Chickens, Domestication, Foraging, Spatial learning, Stress
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-18403 (URN)10.1016/j.beproc.2009.02.005 (DOI)
    Tillgänglig från: 2009-05-25 Skapad: 2009-05-25 Senast uppdaterad: 2009-05-25
    5. Domestication effects on food deprivation induced behaviour in red jungle fowl (Gallus gallus) and White Leghorn layers
    Öppna denna publikation i ny flik eller fönster >>Domestication effects on food deprivation induced behaviour in red jungle fowl (Gallus gallus) and White Leghorn layers
    Manuskript (Övrigt vetenskapligt)
    Identifikatorer
    urn:nbn:se:liu:diva-13002 (URN)
    Tillgänglig från: 2008-03-11 Skapad: 2008-03-11 Senast uppdaterad: 2010-01-13
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    FULLTEXT01
    Ladda ner (pdf)
    COVER01
  • 114.
    Lindqvist, Christina
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Janczak, Andrew M.
    Department of Animal and Aquacultural Sciences, Norwegian University of Life Sciences, Ås, Norway.
    Nätt, Daniel
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Baranowska, Izabella
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Lindqvist, Niclas
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Wichman, Anette
    Department of Animal Environment and Health, Swedish University of Agricultural Sciences, Skara, Sweden.
    Lundeberg, Joakim
    School of Biotechnology, Department of Gene Technology, Royal Institute of Technology, Stockholm, Sweden.
    Lindberg, Johan
    School of Biotechnology, Department of Gene Technology, Royal Institute of Technology, Stockholm, Sweden.
    Torjesen, Peter A.
    Hormone Laboratory, Aker University Hospital HF, Oslo, Norway.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Transmission of Stress-Induced Learning Impairment and Associated Brain Gene Expression from Parents to Offspring in Chickens2007Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 2, nr 4, s. e364-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Stress influences many aspects of animal behaviour and is a major factor driving populations to adapt to changing living conditions, such as during domestication. Stress can affect offspring through non-genetic mechanisms, but recent research indicates that inherited epigenetic modifications of the genome could possibly also be involved.

    Methodology/Principal Findings: Red junglefowl (RJF, ancestors of modern chickens) and domesticated White Leghorn (WL) chickens were raised in a stressful environment (unpredictable light-dark rhythm) and control animals in similar pens, but on a 12/12 h light-dark rhythm. WL in both treatments had poorer spatial learning ability than RJF, and in both populations, stress caused a reduced ability to solve a spatial learning task. Offspring of stressed WL, but not RJF, raised without parental contact, had a reduced spatial learning ability compared to offspring of non-stressed animals in a similar test as that used for their parents. Offspring of stressed WL were also more competitive and grew faster than offspring of non-stressed parents. Using a whole-genome cDNA microarray, we found that in WL, the same changes in hypothalamic gene expression profile caused by stress in the parents were also found in the offspring. In offspring of stressed WL, at least 31 genes were up- or down-regulated in the hypothalamus and pituitary compared to offspring of non-stressed parents.

    Conclusions/ Significance: Our results suggest that, in WL the gene expression response to stress, as well as some behavioural stress responses, were transmitted across generations. The ability to transmit epigenetic information and behaviour modifications between generations may therefore have been favoured by domestication. The mechanisms involved remain to be investigated; epigenetic modifications could either have been inherited or acquired de novo in the specific egg environment. In both cases, this would offer a novel explanation to rapid evolutionary adaptation of a population.

  • 115.
    Lindqvist, Christina
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Jensen , Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Domestication and stress effects on contrafreeloading and spatial learning performance in red jungle fowl (Gallus gallus) and White Leghorn layers2009Ingår i: BEHAVIOURAL PROCESSES, ISSN 0376-6357 , Vol. 81, nr 1, s. 80-84Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    White Leghorn layers (WL) show modified foraging strategies. compared to their ancestor, the red jungle fowl (RJF). Birds selected for high production may invest more resources into production traits and less in other biological Processes. This may affect the capacity to adapt to new or variable environments.

    Thirty birds of each of RJF and WL were raised in a stressful environment (unpredictable light:dark schedule) and 30 control animals of each breed in similar pens, but on a 12:12 h light:dark schedule. We studied the differences between breed and treatment with respect to contrafreeloading (CFL), spatial learning ability and the birds behaviour in a T-maze.

    WL showed less CFL, were less cautious in the test arena and showed an impaired spatial learning ability Compared with RJF in both test situations. Stress impaired spatial learning in both breeds, but stressed RJF showed a more active response to the test situation than non-stressed RJF, by starting to eat faster, while stressed WL prolonged their time to start eating compared to non-stressed WL. Our results may reflect different adaptive Strategies, where RJF appear better adapted to an unpredictable environment.

  • 116.
    Lindqvist, Christina
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Effects of age, sex and social isolation on contrafreeloading in red junglefowl (Gallus gallus) and White Leghorn fowl2008Ingår i: Applied Animal Behaviour Science, ISSN 0168-1591, E-ISSN 1872-9045, Vol. 114, nr 3-4, s. 419-428Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Contrafreeloading (CFL), i.e. choosing to work to obtain food over free food, has been studied in many different species. White Leghorn laying hens selected for high production have a lower extent of CFL compared to their wild ancestor, red junglefowl. We studied the effects of age, sex and social isolation. on the extent of CFL in red junglefowl and White Leghorn layers.

    For 48 h, 30 birds of each breed were allowed a choice, between freely available food and food mixed with wood shavings. Both females and males were tested individually as young birds (8-10 weeks old) and when they were sexually mature (27-29 weeks old). To test the possible effects of social isolation, the same birds were also tested in pairs at 30 weeks of age.

    Junglefowl showed a higher extent of CFL at the younger age compared to Leghorns (33.7% vs. 22.7%: P = 0.05) and both breeds showed higher extent of CFL at a young age than when sexually mature (P < 0.001). There were no significant differences between the two breeds when they were sexually mature and tested individually but, when tested in pairs, junglefowl showed higher extent of CFL than Leghorns (31.7% vs. 17.0%; P < 0.001). There were no differences in the extent of CFL between the sexes in either breed.

    The results indicate that age and social isolation influence the extent of CFL in fowl. Furthermore, the results support earlier findings that the extent of CFL is lower in Leghorns than junglefowl, indicating a possible side-effect of selection for increased production.

  • 117.
    Lindqvist, Christina
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Lind, Jenny
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Jensen , Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Effects of domestication on food deprivation-induced behaviour in red junglefowl, Gallus gallus, and White Leghorn layers2009Ingår i: ANIMAL BEHAVIOUR, ISSN 0003-3472 , Vol. 77, nr 4, s. 893-899Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Domestication and selection for high production have selected animals with less energy-demanding behaviour. In the natural environment of the ancestors, fitness (reproductive success) is often favoured by an ability to locate and remember food sites, whereas in captivity, fitness may be more related to the ability to grow and reproduce efficiently under stable food conditions. We hypothesized that domestication and selection for production traits have caused animals to react less actively to food shortage. In this experiment, 26 red junglefowl (RJF) and 27 White Leghorn layers (WL), the latter selected for high egg production, were exposed to 0, 3 and 24 h of food deprivation while housed in furnished cages. After food deprivation, we quantified the birds behaviour, in a series of tests. Birds of both breeds performed more foraging-exploring, less preening behaviour and less perching with increasing length of food deprivation. However, when tested in a group, RJF showed a more active response than WL to food shortage by reducing perching time and increasing the foraging and exploration time on the ground, which may be interpreted as a more risk-prone behaviour. Furthermore, when tested individually, there was a breed effect on response in the open field and the novel object tests, where RJF were more cautious than WL. The results may reflect different feeding strategies: the behaviour of RJF would probably be more adaptive in a natural environment, while the behaviour shown by WL may allow more investment in production traits in a more predictable environment.

  • 118.
    Lindqvist, Christina
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Zimmerman, Patrick
    University of Bristol, Department of Farm Animal Science, United Kingdom.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    A note on contrafreeloading in broilers compared to layer chicks2006Ingår i: Applied Animal Behaviour Science, ISSN 0168-1591, Vol. 101, nr 1-2, s. 161-166Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Contrafreeloading (CFL) is the behaviour where an animal chooses to work for food even when identical food can be obtained without any effort. Previous studies have suggested that the difference in CFL between White Leghorn layers and jungle fowl may be a side effect of selection for increased production traits in the Leghorn strain.

    In this experiment we studied to what extent broilers chicks (Cobb/Ross), which are highly selected for fast growth, perform CFL and compared this with a layer strain (Calder Ranger), which grows considerably slower. We predicted that broilers should have a lower degree of CFL compared to the layer strain, as an energy-saving response to the demands of rapid growth.

    During 48 h 10 pairs of each breed were given a choice between freely available food and food mixed with wood shavings. Behavioural observations were made twice each day. Broilers showed less CFL (p < 0.05), were more inactive (p < 0.001) and performed less active behaviours (p < 0.05) than layers.

    Our results support previous findings that decreased CFL in domestic fowl may indicate adaptive reallocation of energy resources in response to selection for increased production traits.

  • 119.
    Lunneryd, Sven Gunnar
    et al.
    National Board of Fisheries, Tja¨rno¨ Marine Biological Laboratory, SE-452 96 Strömstad, Sweden.
    Fjälling, Arne
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Westerberg, Håkan
    National Board of Fisheries, Box 423, SE-401 26 Gothenburg, Sweden..
    A large-mesh salmon trap: a way of mitigating seal impact on a coastal fishery2003Ingår i: ICES Journal of Marine Science, ISSN 1054-3139, E-ISSN 1095-9289, Vol. 60, nr 6, s. 1194-1199Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A new design for a salmon trap aimed at minimizing damage to catch and gear caused by grey seals was tested. The traditional trap design used in the northern Baltic permits an efficient hunting strategy by seals, whereby chased fish entangle themselves in the side panels and can then easily be taken, with associated damage to the net. The side panels of the test trap (excluding the fish chamber) are made of large-mesh (400 mm) netting compared to ≤200 mm in traditional traps. This should allow seal-chased and panicking salmon to pass through, while less stressed individuals should still be guided efficiently towards the fish chamber. Trials with the two trap types were performed at the mouth of the river Indal (northern Sweden) in a comparative test programme. Catches of salmon and trout in the test trap were larger than in the standard trap. We estimated that 65% of the potential catch was lost in the standard trap owing to seal predation, while escape rate through the large meshes in the test trap was 52%. The standard trap had a total of 269 holes owing to seal damage, while only six holes were found in the test trap. Seal activity in and around the standard trap was up to 16 times higher compared with the test trap and decreased considerably during the following year when only large-meshed traps were used in the area. We suggest that seals are difficult to deter from fishing gear as long as they get a reward in terms of food and propose that a strategy that deprives seals of a reward will make the gear uninteresting to them and may have long-term mitigation effects.

  • 120.
    Løtvedt, Pia Katrine
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska högskolan.
    Murali, Sathish Kumar
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska högskolan.
    Hernandez Salazar, Laura Teresa
    Instituto de Neuro-Etologia, Universidad Veracruzana, 91000 Xalapa, Veracruz, Mexico.
    Laska, Matthias
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Olfactory sensitivity for "green odors" (Aliphatic C6 Alcohols and C6 aldehydes) - A comparative study in male CD-1 mice (Mus musculus) and female spides monkeys (Ateles geoffroyi)2012Ingår i: Pharmacology, Biochemistry and Behavior, ISSN 0091-3057, E-ISSN 1873-5177, Vol. 101, nr 3, s. 450-457Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Using a conditioning paradigm, the olfactory sensitivity of six male CD-1 mice for “green odors”, a group of eightstructurally related aliphatic C6 alcohols and aldehydes known to exert anxiolytic and stress-reducing effects,was investigated. With all eight stimuli, the animals discriminated concentrations!0.03 ppm(parts per million)from the solvent, and with three of the eight stimuli the best-scoring animals were even able to detect concen-trations !0.03 ppb (parts per billion). Three female spider monkeys tested in parallel were found to detect thesame eight stimuli at concentrations b1 ppm, and with six of the eight stimuli the best-scoring animals detectedconcentrations !0.1 ppm. Analysis of odor structure–activity relationships showed that in both species the typeof functional group attached to the aliphatic C6 backbone of the odorant molecules systematically affected theirolfactory sensitivity whereas the presence/absence of a double bond did not. In the mice, but not in the spidermonkeys, the position of a double bond and the cis/trans-configuration of the odorant molecules also had a sys-tematic effect on detectability of the “green odors”. A comparison of the detection thresholds between the twospecies tested here and those obtained in human subjects suggests that the number of functional olfactory recep-tor genes is a poor predictor of a species' olfactory sensitivity for “green odors”.

  • 121.
    Macdonald, Barry
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi.
    The effects of early stress on life-time strategies of behaviour and coping in chickens ( Gallus gallus )2011Självständigt arbete på avancerad nivå (masterexamen), 60 poäng / 90 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Stress is often an important consideration for animal welfare. A number of factors can contribute to stress in domestic animals, most notably thoseused in food production. We investigated the effects and heritability of stress in domestic chickens (Gallus gallus). Using a spatial learning paradigm, we tested an early social isolation-stressed group and their offspring against unstressed controls, to determine if this cognitive function was negatively affected by stress. In the parental generation, we found that across sessions control birds improved in performance, indicating a learning trend. Stressed birds showed no difference across sessions, indicating a lack of learning. No effects of the parental treatment were found in the offspring of stress and control birds. Social isolation stress was found to affect spatial memory learning, however, we did not find evidence that the parental stress influenced the spatial abilities of the next generation despite changes in other behaviours.

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  • 122. Mayntz, Michael
    et al.
    Sender, Grazyna
    Andersson, Annelie
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi.
    Sederstrom, Roger
    The influence of milk withdrawal, stable routines and separation from dam on suckling behaviour of Hereford calves2006Ingår i: Archiv für Tierzucht, engelsk paralleltittel, ISSN 0003-9438, Vol. 49, nr 6, s. 545-560Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The influence of milk withdrawal, stable routines and separation from dam on suckling behaviour of beef calves was tested in an 8x8 Latin square experiment. Length of the meal and length of the longest bout were measured to describe the meal as a whole. Length of pre-stimulation, increasing ejection, declining ejection, and after stimulation were measured to describe the structure of meal. Eagerness of suckling was described as relative suckling time and non-suckling. Milk withdrawal increased length of meal and longest bout, but did not influence structure of meal. Milk withdrawal resulted in cistern-milk being available already before ejection and thereby in longer bouts during pre-stimulation. Milk withdrawal had no influence on eagerness of suckling. Stable routines had no influence on meal as a whole, but increased pre- and decreased after-stimulation and tended to result in somewhat longer bouts during pre-stimulation. There was no influence of stable routines on eagerness of suckling. Separation from dam had no influence on meal as a whole or structure of meal, but increased eagerness of suckling for the whole meal and for almost all periods. The experimental results partially sustained results from a field study.

  • 123.
    Mello, I.
    et al.
    University of Algarve, Faculty of Sea Sciences and Environment, Faro, Portugal, Kolmården Wild Animal Park, Research and Education Center, 618 92 Kolmården, Sweden.
    Nordensten, L.
    Amundin, Mats
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Reactions of three bottlenose dolphin dams with calves to other members of the group in connection with nursing2005Ingår i: Zoo Biology, ISSN 0733-3188, E-ISSN 1098-2361, Vol. 24, nr 6, s. 543-555Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The suckling behavior of three bottlenose dolphin (Tursiops truncatus) mother-calf pairs at the Kolmården Wild Animal Park, Sweden, was followed from birth until the calves were 1 year old, with emphasis on the behavior of the mothers toward other dolphins present in pool. The results show that 80.44% of the sucklings occurred when the dams were not accompanied by another member of the group. This preference declined, as the calf grew older, for all three dams. Three factors influenced this company preference in relation to nursing and contributed to the total variance in a detectable way: the month post partum, company preference, and the mother's ID, i.e., which mother was involved. The time between the category "dam leaves company" and the beginning of nursing increased over the months for all three dams. These results indicate that another dolphin is not automatically an asset to a dam with a newborn, and that, in human care, ample space and limited number of pool mates must be provided to allow the dam the necessary privacy in connection with nursing. © 2005 Wiley-Liss, Inc.

  • 124.
    Mignon-Grasteau, S.,
    et al.
    Station de Recherches Avicoles INRA, France.
    Boissy, A.,
    Unite´ de Recherches sur les Herbivores INRA, France.
    Bouixc, J.,
    Station d¿Ame´lioration Ge´ne´tique des Animaux INRA, France.
    Faure, J.M.,
    Station de Recherches Avicoles INRA, France.
    Fisherd, A.D.,
    CSIRO Livestock Industries FD McMaster Laboratory, Australia.
    Hinch, G.N.,
    School of Rural Science and Agriculture University of New England, Australia.
    Jensen, Per
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi.
    Le Neindre, P.,
    Unite´ de Recherches sur les Herbivores INRA, France.
    Morméde, P.,
    Laboratoire de Neuroge´ne´tique et Stres INRA, France.
    Pruneth, P.,
    Physiologie des Poissons INRA, France.
    Vandeputte, M.,
    Ge´ne´tique des poissons INRA, France.
    Beaumont, C.,
    Station de Recherches Avicoles INRA, France.
    Genetics of adaptation and domestication in livestock2005Ingår i: Livestock Production Science, ISSN 0301-6226, E-ISSN 1872-6070, Vol. 93Artikel i tidskrift (Refereegranskat)
  • 125.
    Milberg, Per
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ekologi. Linköpings universitet, Tekniska högskolan.
    Altimiras, Jordi
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Amundin, M
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Bergman, Karl-Olof
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ekologi. Linköpings universitet, Tekniska högskolan.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Wahlström, Dan
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ekologi. Linköpings universitet, Tekniska högskolan.
    Precision i poängsättning av essäfrågor och examensarbeten: implikationer för betyg enligt ECTS2006Ingår i: Nya vilkor för lärande och undervisning. 9:e universitetspedagogiska konferensen vid Linköpings universitet 17 oktober 2005,2005, Linköping: Linköpings universitet , 2006, s. 167-Konferensbidrag (Refereegranskat)
  • 126.
    Moe, Randi Opperman
    et al.
    School of Veterinary Science, Oslo, Norway.
    Nordgreen, Janicke
    School of Veterinary Science, Oslo, Norway.
    Janczak, Andrew M.
    School of Veterinary Science, Oslo, Norway.
    Bakken, Morten
    NMBU, Department of Animal and Aquacultural Sciences, Aas, Norway.
    Spruijt, Berry M
    University of Utrecht, The Netherlands.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska högskolan.
    Anticipatory and foraging behaviors in response to palatable food rewardin chickens: Effects of dopamine D2 receptor blockade and domestication2014Ingår i: Physiology and Behavior, ISSN 0031-9384, E-ISSN 1873-507X, Vol. 133, s. 170-177Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Behaviors associatedwith anticipation and search for palatable foodmay provide information about dopaminergicreward processes and positivemotivational affect in animals. The overall aimwas to investigate the involvement ofdopamine signaling in the regulation of cue-induced anticipation and search for palatable food reward in chicken,and whether domestication has affected expression of reward-related behaviors. The specific aimswere to describeeffects of mealworms (palatable food for hens) and haloperidol (a dopamine D2 antagonist) onforaging behaviors and cue-induced anticipatory behaviors in Red Junglefowl (RJF; the wild ancestor of modernlaying hens) and awhite layer hybrid (LSL). RJF (n=26) and LSL (n=20)were initially trained on a conditioningschedule to anticipate mealworms (unconditioned stimulus; US) 25 s after exposure to a red light (conditionedstimulus; CS). For the experiment, hens received haloperidol or saline injections 30 min before exposure to oneCS + US combination. Behavior was registered 10 min before CS and 10 min after US (foraging behaviors), andduring the CS–US interval (anticipatory behaviors). Higher frequencies of CS-induced anticipatory head movements,faster approach to rewards, and higher frequency of foraging behaviors were found in LSL compared toRJF. Haloperidol suppressed CS-induced headmovements in both breeds, and the frequency of foraging behaviorsafter reward delivery. The results support a role of dopamine signaling in the regulation of reward processes inchickens, and suggest that domestication has changed the threshold for perceiving food incentives and/or forexpressing reward-related behaviors that may be indicative of positive motivational affect in hens.

  • 127.
    Nachtigal, Paul E.
    et al.
    Hawaii Institute of Marine Biology, University of Hawaii.
    Supin, Alexander Y.
    Russian Academy of Sciences, Moscow.
    Amundin, Mats
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Röken, Bengt
    Kolmårdens Djurpark .
    Möller, Thorsten
    Kolmårdens Djurpark .
    Mooney, T. Aran
    Hawaii Institute of Marine Biology, University of Hawaii.
    Taylor, Kristen A.
    Hawaii Institute of Marine Biology, University of Hawaii.
    Yuen, Michelle
    Pacific Islands Regional Office, Honolulu.
    Polar bear Ursus maritimus hearing measured with auditory evoked potentials2007Ingår i: Journal of Experimental Biology, ISSN 0022-0949, E-ISSN 1477-9145, Vol. 210, s. 1116-1122Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    While there has been recent concern about the effects of sound on marine mammals, including polar bears, there are no data available measuring the hearing of any bear. The in-air hearing of three polar bears was measured using evoked auditory potentials obtained while tone pips were played to three individually anaesthetized bears at the Kolmården Djurpark. Hearing was tested in half-octave steps from 1 to 22.5 kHz. Measurements were not obtainable at 1 kHz and best sensitivity was found in the range from 11.2–22.5 kHz. Considering the tone pips were short and background noise measurements were available, absolute measurements were estimated based on an assumed mammalian integration time of 300 ms. These data show sensitive hearing in the polar bear over a wide frequency range and should cause those concerned with the introduction of anthropogenic noise into the polar bear's environment to operate with caution.

  • 128. Beställ onlineKöp publikationen >>
    Nätt, Daniel
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Heritable epigenetic responses to environmental challenges: Effects on behaviour, gene expression and DNA-methylation in the chicken2011Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Phenotypic variation within populations is a crucial factor in evolution and is mainly thought to be driven by heritable changes in the base sequence of DNA. Among our domesticated species we find some of the most variable species on earth today. This variety of breeds has appeared during a relatively short evolutionary time, and so far genetic studies have been unable to explain but a small portion of this variation, which indicates more novel mechanisms of inheritance and phenotypic plasticity. The aim of this study was therefore to investigate some of these alternative routes in the chicken, especially focusing on transgenerational effects of environmental challenges on behaviour and gene expression in relation to domestication. In two experiments a chronically unpredictable environment induced phenotypic changes in the parents that were mirrored in the unexposed offspring raised without parental contact. This transmission was especially clear in domesticated birds. A third experiment showed that repeated stress events very early in life could change the developmental program making the birds more resistant to stress later in life. Here, the phenotypic changes were also mirrored in the unexposed offspring and associated with inheritance of gene expression. Epigenetic factors, such as DNA-methylation, could play an important role in the mechanism of these transgenerational effects. A fourth experiment showed that wild types and domesticated chickens differed substantially in their patterns of DNA-methylation, where the domesticated breed had increased amount of promoter DNA-methylation. In line with the previous experiments, this breed also showed increased transmission of methylation marks to their  offspring. Conclusively, parental exposure of environmental challenges that introduce changes in behaviour, physiology and gene expression can under both chronic and temporal conditions be heritably programmed in the parent and transmitted to the unexposed offspring. Since heritable epigenetic variation between wild type and domesticated chickens is stable and numerous, it is possible that selection for favourable epigenomes could add another level to the evolutionary processes and therefore might explain some of the rapid changes in the history of the domesticated chicken. 

    Delarbeten
    1. Transmission of Stress-Induced Learning Impairment and Associated Brain Gene Expression from Parents to Offspring in Chickens
    Öppna denna publikation i ny flik eller fönster >>Transmission of Stress-Induced Learning Impairment and Associated Brain Gene Expression from Parents to Offspring in Chickens
    Visa övriga...
    2007 (Engelska)Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 2, nr 4, s. e364-Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Background: Stress influences many aspects of animal behaviour and is a major factor driving populations to adapt to changing living conditions, such as during domestication. Stress can affect offspring through non-genetic mechanisms, but recent research indicates that inherited epigenetic modifications of the genome could possibly also be involved.

    Methodology/Principal Findings: Red junglefowl (RJF, ancestors of modern chickens) and domesticated White Leghorn (WL) chickens were raised in a stressful environment (unpredictable light-dark rhythm) and control animals in similar pens, but on a 12/12 h light-dark rhythm. WL in both treatments had poorer spatial learning ability than RJF, and in both populations, stress caused a reduced ability to solve a spatial learning task. Offspring of stressed WL, but not RJF, raised without parental contact, had a reduced spatial learning ability compared to offspring of non-stressed animals in a similar test as that used for their parents. Offspring of stressed WL were also more competitive and grew faster than offspring of non-stressed parents. Using a whole-genome cDNA microarray, we found that in WL, the same changes in hypothalamic gene expression profile caused by stress in the parents were also found in the offspring. In offspring of stressed WL, at least 31 genes were up- or down-regulated in the hypothalamus and pituitary compared to offspring of non-stressed parents.

    Conclusions/ Significance: Our results suggest that, in WL the gene expression response to stress, as well as some behavioural stress responses, were transmitted across generations. The ability to transmit epigenetic information and behaviour modifications between generations may therefore have been favoured by domestication. The mechanisms involved remain to be investigated; epigenetic modifications could either have been inherited or acquired de novo in the specific egg environment. In both cases, this would offer a novel explanation to rapid evolutionary adaptation of a population.

    Nyckelord
    Stress, Prenatal stress, Animal behaviour, Gene expresssion, Domestication, Chicken, Red junglefowl, White Leghorn, Epigenetics, Transgenerational effects, Epigenetic inheritance, Maternal effects, Paternal effects
    Identifikatorer
    urn:nbn:se:liu:diva-15529 (URN)10.1371/journal.pone.0000364 (DOI)
    Tillgänglig från: 2008-11-17 Skapad: 2008-11-14 Senast uppdaterad: 2019-03-05Bibliografiskt granskad
    2. Inheritance of Acquired Behaviour Adaptions and Brain Gene Expression in Chickens
    Öppna denna publikation i ny flik eller fönster >>Inheritance of Acquired Behaviour Adaptions and Brain Gene Expression in Chickens
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    2009 (Engelska)Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 4, nr 7, s. e6405-Artikel, forskningsöversikt (Övrigt vetenskapligt) Published
    Abstract [en]

    Background: Environmental challenges may affect both the exposed individuals and their offspring. We investigated possible adaptive aspects of such cross-generation transmissions, and hypothesized that chronic unpredictable food access would cause chickens to show a more conservative feeding strategy and to be more dominant, and that these adaptations would be transmitted to the offspring.

    Methodology/Principal Findings: Parents were raised in an unpredictable (UL) or in predictable diurnal light rhythm (PL, 12:12 h light:dark). In a foraging test, UL birds pecked more at freely available, rather than at hidden and more attractive food, compared to birds from the PL group. Female offspring of UL birds, raised in predictable light conditions without parental contact, showed a similar foraging behavior, differing from offspring of PL birds. Furthermore, adult offspring of UL birds performed more food pecks in a dominance test, showed a higher preference for high energy food, survived better, and were heavier than offspring of PL parents. Using cDNA microarrays, we found that the differential brain gene expression caused by the challenge was mirrored in the offspring. In particular, several immunoglobulin genes seemed to be affected similarly in both UL parents and their offspring. Estradiol levels were significantly higher in egg yolk from UL birds, suggesting one possible mechanism for these effects.

    Conclusions/Significance: Our findings suggest that unpredictable food access caused seemingly adaptive responses in feeding behavior, which may have been transmitted to the offspring by means of epigenetic mechanisms, including regulation of immune genes. This may have prepared the offspring for coping with an unpredictable environment.

    Citation: Nätt D, Lindqvist N, Stranneheim H, Lundeberg J, Torjesen PA, et al. (2009) Inheritance of Acquired Behaviour Adaptations and Brain Gene Expression in Chickens. PLoS ONE 4(7): e6405. doi:10.1371/journal.pone.0006405

    Editor: Tom Pizzari, University of Oxford, United Kingdom

    Received: March 26, 2009; Accepted: June 30, 2009; Published: July 28, 2009

    Copyright: © 2009 Nätt et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

    Funding: This project was funded by the Swedish Research Council (VR; www.vr.se; grant nrs 50280101 and 50280102) and the Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning (Formas; www.formas.se; grant no 221-2005-270). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the mauscript.

    Competing interests: The authors have declared that no competing interests exist.

     

    Nationell ämneskategori
    Biologiska vetenskaper
    Identifikatorer
    urn:nbn:se:liu:diva-19948 (URN)10.1371/journal.pone.0006405 (DOI)
    Anmärkning
    Original Publication: Daniel Nätt, Niclas Lindqvist, Henrik Stranneheim, Joakim Lundeberg, Peter A. Torjesen and Per Jensen, Inheritance of Acquired Behaviour Adaptions and Brain Gene Expression in Chickens, 2009, PLoS ONE, (4), 7, e6405. http://dx.doi.org/10.1371/journal.pone.0006405 Copyright: Authors Tillgänglig från: 2009-08-25 Skapad: 2009-08-19 Senast uppdaterad: 2019-03-05Bibliografiskt granskad
    3. Transgenerational effects of early experience on acute stress reactions in behaviour, steroid hormones and gene expression in the precocial chicken
    Öppna denna publikation i ny flik eller fönster >>Transgenerational effects of early experience on acute stress reactions in behaviour, steroid hormones and gene expression in the precocial chicken
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    2012 (Engelska)Ingår i: Hormones and Behavior, ISSN 0018-506X, E-ISSN 1095-6867, Vol. 61, nr 5, s. 711-718Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Stress during early life can profoundly influence an individual’s phenotype. Effects can manifest in the short-term as well as later in life and even in subsequent generations. Transgenerational effects of stress are potentially mediated via modulation of the hypothalamic-pituitary-adrenal axis (HPA) as well as epigenetic mechanisms causing heritable changes in gene expression. To investigate these pathways we subjected domestic chicks (Gallus gallus) to intermittent social isolation, food restriction, and temperature stress for the first three weeks of life. The early life stress resulted in a dampened corticosterone response to restraint stress in the parents and male offspring. Stress-specific genes, such as early growth response 1 (EGR1) and corticotropin releasing hormone receptor 1 (CRHR1), were upregulated when chicks were tested in the context of restraint stress, but not under baseline conditions. Treatment differences in gene expression were also correlated across generations which indicate transgenerational epigenetic inheritance, possibly mediated by differences in maternal yolk estradiol and testosterone. In an associative learning test early stressed birds made more correct choices suggesting a higher coping ability in stressful situations. This study is the first to show transgenerational effects of early life stress in a precocial species by combining behavioural, endocrinological, and transcriptomic measurements.

    Nyckelord
    Early growth response, corticotropin releasing hormone receptor, postnatal stress, behaviour, epigenetics, transgenerational effects, steroid hormones, gene expression
    Nationell ämneskategori
    Biologiska vetenskaper
    Identifikatorer
    urn:nbn:se:liu:diva-70157 (URN)10.1016/j.yhbeh.2012.03.006 (DOI)000304339800007 ()
    Anmärkning
    funding agencies|Swedish Research Council||Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning||Tillgänglig från: 2011-08-22 Skapad: 2011-08-22 Senast uppdaterad: 2019-03-05
    4. Heritable genome-wide variation of gene expression and promoter methylation between wild and domesticated chickens
    Öppna denna publikation i ny flik eller fönster >>Heritable genome-wide variation of gene expression and promoter methylation between wild and domesticated chickens
    Visa övriga...
    2012 (Engelska)Ingår i: BMC Genomics, ISSN 1471-2164, E-ISSN 1471-2164, Vol. 13, nr 59Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Variations in gene expression, mediated by epigenetic mechanisms, may cause broad phenotypic effects in animals. However, it has been debated to what extent expression variation and epigenetic modifications, such as patterns of DNA methylation, are transferred across generations, and therefore it is uncertain what role epigenetic variation may play in adaptation. Here, we show that in Red Junglefowl, ancestor of domestic chickens, gene expression and methylation profiles in thalamus/hypothalamus differ substantially from that of a domesticated egg laying breed. Expression as well as methylation differences are largely maintained in the offspring, demonstrating reliable inheritance of epigenetic variation. Some of the inherited methylation differences are tissue-specific, and the differential methylation at specific loci are little changed after eight generations of intercrossing between Red Junglefowl and domesticated laying hens. There was an over-representation of differentially expressed and methylated genes in selective sweep regions associated with chicken domestication. Hence, our results show that epigenetic variation is inherited in chickens, and we suggest that selection of favourable epigenomes, either by selection of genotypes affecting epigenetic states, or by selection of methylation states which are inherited independently of sequence differences, may have been an important aspect of chicken domestication.

    Ort, förlag, år, upplaga, sidor
    BioMed Central, 2012
    Nyckelord
    Domestication, gene expression, tiling array, behaviour, methylation
    Nationell ämneskategori
    Biologiska vetenskaper
    Identifikatorer
    urn:nbn:se:liu:diva-70159 (URN)10.1186/1471-2164-13-59 (DOI)000301440800001 ()
    Anmärkning

    funding agencies|Swedish Research Council| 2008-14496-59340-36 |Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning| 221 2007 838 |

    Tillgänglig från: 2011-08-22 Skapad: 2011-08-22 Senast uppdaterad: 2019-03-05Bibliografiskt granskad
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    Heritable epigenetic responses to environmental challenges
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    omslag
  • 129. Beställ onlineKöp publikationen >>
    Nätt, Daniel
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Stress and the Offspring: Adaptive Transgenerational Effects of Unpredictability on Behaviour and Gene Expression in Chickens (Gallus gallus)2008Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Environmental stress has shown to affect both the exposed individuals and the development of their offspring. Generally, it is thought that the stressed organism responds to stress by trying to adapt to it. This thesis investigates possible evolutionary consequences of cross-generational transmissions of stress, where the parent has been stressed but the offspring has not. In two studies we have exposed chicken parents of different breeds to an unpredictable circadian light rhythm, to investigate the influence of genetic background on the transmission of behaviour and patterns of genome-wide gene expression across generations. In Paper I, we can show that the domesticated chicken, by means of epigenetic factors, transmit their behaviours as well as their gene expression profiles to their offspring to a higher extent than their wild ancestor, the red junglefowl. Furthermore, in Paper II, even though the offspring never experienced the stress or had any contact with their stressed parents, they seemed to have adapted to it, which suggests that the parents might have prepared (or pre-adapted) them for living in the unpredictable environment. Additionally, eggs of stressed hens showed increased levels of estradiol that might have affected gene expression of specific immune genes, which were up-regulated in the offspring of stressed parents. It is possible that the traditional distinction between stress responses and evolutionary adaptation may be reevaluated, since our results indicate that they could be parts of the same evolutionary event.

    Delarbeten
    1. Transmission of Stress-Induced Learning Impairment and Associated Brain Gene Expression from Parents to Offspring in Chickens
    Öppna denna publikation i ny flik eller fönster >>Transmission of Stress-Induced Learning Impairment and Associated Brain Gene Expression from Parents to Offspring in Chickens
    Visa övriga...
    2007 (Engelska)Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 2, nr 4, s. e364-Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Background: Stress influences many aspects of animal behaviour and is a major factor driving populations to adapt to changing living conditions, such as during domestication. Stress can affect offspring through non-genetic mechanisms, but recent research indicates that inherited epigenetic modifications of the genome could possibly also be involved.

    Methodology/Principal Findings: Red junglefowl (RJF, ancestors of modern chickens) and domesticated White Leghorn (WL) chickens were raised in a stressful environment (unpredictable light-dark rhythm) and control animals in similar pens, but on a 12/12 h light-dark rhythm. WL in both treatments had poorer spatial learning ability than RJF, and in both populations, stress caused a reduced ability to solve a spatial learning task. Offspring of stressed WL, but not RJF, raised without parental contact, had a reduced spatial learning ability compared to offspring of non-stressed animals in a similar test as that used for their parents. Offspring of stressed WL were also more competitive and grew faster than offspring of non-stressed parents. Using a whole-genome cDNA microarray, we found that in WL, the same changes in hypothalamic gene expression profile caused by stress in the parents were also found in the offspring. In offspring of stressed WL, at least 31 genes were up- or down-regulated in the hypothalamus and pituitary compared to offspring of non-stressed parents.

    Conclusions/ Significance: Our results suggest that, in WL the gene expression response to stress, as well as some behavioural stress responses, were transmitted across generations. The ability to transmit epigenetic information and behaviour modifications between generations may therefore have been favoured by domestication. The mechanisms involved remain to be investigated; epigenetic modifications could either have been inherited or acquired de novo in the specific egg environment. In both cases, this would offer a novel explanation to rapid evolutionary adaptation of a population.

    Nyckelord
    Stress, Prenatal stress, Animal behaviour, Gene expresssion, Domestication, Chicken, Red junglefowl, White Leghorn, Epigenetics, Transgenerational effects, Epigenetic inheritance, Maternal effects, Paternal effects
    Identifikatorer
    urn:nbn:se:liu:diva-15529 (URN)10.1371/journal.pone.0000364 (DOI)
    Tillgänglig från: 2008-11-17 Skapad: 2008-11-14 Senast uppdaterad: 2019-03-05Bibliografiskt granskad
    2. Transgenerational Phenotypic Tuning of Offspring: Adaptive Responses to a Prenatal Environmental Challenge in Chickens
    Öppna denna publikation i ny flik eller fönster >>Transgenerational Phenotypic Tuning of Offspring: Adaptive Responses to a Prenatal Environmental Challenge in Chickens
    Visa övriga...
    2008 (Engelska)Manuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Stress may affect both the exposed individuals and the development of their offspring. We have previously shown that offspring of stressed domestic chickens can inherit the stressed-induced learning impairments of their parents and the associated modifications in brain gene expression. In this study we investigated possible adaptive aspects of such cross-generation transmissions. We hypothesized that stress would cause chickens to show a more conservative feeding strategy and to be more dominant, and that these adaptations would be transmitted to the offspring. Parents were raised in an unpredictable diurnal light rhythm (stress treatment) or in control conditions (12:12 h light:dark). In a foraging test, stressed birds pecked more at freely available than at hidden and more attractive food compared to birds from the control group. Female offspring of stressed birds, raised in control conditions without parental contact, showed a similar foraging behavior, differing from offspring of control birds. Furthermore, adult offspring of stressed birds performed more food pecks in a dominance test, showed a higher preference for high energy food, survived better, and were heavier than offspring of control parents. One possible explanation for the more dominant behavior of these birds might be increased androgen/estrogen effects from the yolk during their embryonic phase leading to increased anabolism and androgenic behavior. Using cDNA microarrays, we found that some of the differential brain gene expression caused by stress tended to be mirrored in the offspring, indicating transgenerational effects.  In particular, several immunoglobulin genes seemed to be affected similarly in both stressed parents and their offspring. Estradiol, but not corticoserone, testosterone, androstendion, or dihydrotestosterone, was significantly higher in egg yolk from stressed birds, suggesting a possible mechanism for these effects. Our findings suggest that stress may cause adaptive responses in feeding behavior, which may be transmitted to the offspring by means of epigenetic regulation of immune genes. This may in turn prepare the offspring for coping with an unpredictable environment.

    Förlag
    s. 59
    Nyckelord
    Stress, Prenatal stress, Adaptation, Animal behaviour, Gene expresssion, Microarray, Domestication, Chicken, Epigenetics, Transgenerational effects, Estradiol, Steroid hormones, Epigenetic inheritance, Maternal effects, Paternal effects
    Identifikatorer
    urn:nbn:se:liu:diva-15530 (URN)978-91-7393-753-5 (ISBN)
    Tillgänglig från: 2008-11-17 Skapad: 2008-11-14 Senast uppdaterad: 2019-03-05Bibliografiskt granskad
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    FULLTEXT01
  • 130.
    Nätt, Daniel
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska högskolan.
    Agnvall, Beatrix
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska högskolan.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska högskolan.
    Large Sex Differences in Chicken Behavior and Brain Gene Expression Coincide with Few Differences in Promoter DNA-Methylation2014Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 9, nr 4, s. e96376-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    While behavioral sex differences have repeatedly been reported across taxa, the underlying epigenetic mechanisms in thebrain are mostly lacking. Birds have previously shown to have only limited dosage compensation, leading to high sex bias ofZ-chromosome gene expression. In chickens, a male hyper-methylated region (MHM) on the Z-chromosome has beenassociated with a local type of dosage compensation, but a more detailed characterization of the avian methylome islimiting our interpretations. Here we report an analysis of genome wide sex differences in promoter DNA-methylation andgene expression in the brain of three weeks old chickens, and associated sex differences in behavior of Red Junglefowl(ancestor of domestic chickens). Combining DNA-methylation tiling arrays with gene expression microarrays we show that aspecific locus of the MHM region, together with the promoter for the zinc finger RNA binding protein (ZFR) gene onchromosome 1, is strongly associated with sex dimorphism in gene expression. Except for this, we found few differences inpromoter DNA-methylation, even though hundreds of genes were robustly differentially expressed across distantly relatedbreeds. Several of the differentially expressed genes are known to affect behavior, and as suggested from their functionalannotation, we found that female Red Junglefowl are more explorative and fearful in a range of tests performed throughouttheir lives. This paper identifies new sites and, with increased resolution, confirms known sites where DNA-methylationseems to affect sexually dimorphic gene expression, but the general lack of this association is noticeable and strengthensthe view that birds do not have dosage compensation.

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    fulltext
  • 131.
    Nätt, Daniel
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Andersson, Leif
    Department of Animal Breeding and Genetics Uppsala Biomedical Center, Sweden.
    Kerje, Susanne
    Department of Animal Breeding and Genetics Uppsala Biomedical Center, Sweden.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Plumage Color and Feather Pecking-Behavioral Differences Associated with PMEL17 Genotypes in Chicken (Gallus gallus)2007Ingår i: Behavior Genetics, ISSN 0001-8244, E-ISSN 1573-3297, Vol. 37, nr 2, s. 399-407Artikel i tidskrift (Refereegranskat)
    Abstract [en]

       An F 5 generation of an advanced inter-cross between red junglefowl (wild-type) and White Leghorn (domesticated) was used to investigate earlier findings suggesting that a mutation in the plumage color gene PMEL17 protects against victimization to feather pecking (FP). F 4 parents were selected according to genotype to produce PMEL17 homozygous offspring (i/i and I/I respectively). Birds were raised and their behavior recorded in groups of either two wild-type i/i (dark colored) and one white I/I, or two I/I and one i/i. In addition each bird was tested for feather preference, reaction to novelty, open-field activity, fear for humans, and tonic-immobility. In the home-pens, i/i birds were more feather pecked and had poorer feather condition than I/I birds. No pecking preference for immobile dark colored feathers was observed. In the open-field test i/i birds vocalized more and earlier than I/I birds, and in the fear-for-human test I/I birds had higher activity at 21 weeks of age. No other behavior differences were observed, but clearly, genotypes of PMEL17 affected some aspects of behavior. Such behavioral differences might be important aspects of the mechanism which predispose i/i individuals for being victims of FP.

  • 132.
    Nätt, Daniel
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Lindqvist, Niclas
    Paul-Flechsig-Institute for Brain Research, University of Leipzig, Leipzig, Germany.
    Stranneheim, Henrik
    Royal Institute of Technology, Stockholm.
    Lundeberg, Joakim
    Royal Institute of Technology, Stockholm.
    Torjesen, Peter A.
    Aker University Hospital HF.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Inheritance of Acquired Behaviour Adaptions and Brain Gene Expression in Chickens2009Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 4, nr 7, s. e6405-Artikel, forskningsöversikt (Övrigt vetenskapligt)
    Abstract [en]

    Background: Environmental challenges may affect both the exposed individuals and their offspring. We investigated possible adaptive aspects of such cross-generation transmissions, and hypothesized that chronic unpredictable food access would cause chickens to show a more conservative feeding strategy and to be more dominant, and that these adaptations would be transmitted to the offspring.

    Methodology/Principal Findings: Parents were raised in an unpredictable (UL) or in predictable diurnal light rhythm (PL, 12:12 h light:dark). In a foraging test, UL birds pecked more at freely available, rather than at hidden and more attractive food, compared to birds from the PL group. Female offspring of UL birds, raised in predictable light conditions without parental contact, showed a similar foraging behavior, differing from offspring of PL birds. Furthermore, adult offspring of UL birds performed more food pecks in a dominance test, showed a higher preference for high energy food, survived better, and were heavier than offspring of PL parents. Using cDNA microarrays, we found that the differential brain gene expression caused by the challenge was mirrored in the offspring. In particular, several immunoglobulin genes seemed to be affected similarly in both UL parents and their offspring. Estradiol levels were significantly higher in egg yolk from UL birds, suggesting one possible mechanism for these effects.

    Conclusions/Significance: Our findings suggest that unpredictable food access caused seemingly adaptive responses in feeding behavior, which may have been transmitted to the offspring by means of epigenetic mechanisms, including regulation of immune genes. This may have prepared the offspring for coping with an unpredictable environment.

    Citation: Nätt D, Lindqvist N, Stranneheim H, Lundeberg J, Torjesen PA, et al. (2009) Inheritance of Acquired Behaviour Adaptations and Brain Gene Expression in Chickens. PLoS ONE 4(7): e6405. doi:10.1371/journal.pone.0006405

    Editor: Tom Pizzari, University of Oxford, United Kingdom

    Received: March 26, 2009; Accepted: June 30, 2009; Published: July 28, 2009

    Copyright: © 2009 Nätt et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

    Funding: This project was funded by the Swedish Research Council (VR; www.vr.se; grant nrs 50280101 and 50280102) and the Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning (Formas; www.formas.se; grant no 221-2005-270). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the mauscript.

    Competing interests: The authors have declared that no competing interests exist.

     

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  • 133.
    Nätt, Daniel
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Rubin, Carl-Johan
    Department of Medical Biochemistry and Microbiology, Uppsala University, Sweden.
    Wright, Dominic
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Johnsson, Martin
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Beltéky, Johan
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Andersson, Leif
    Department of Medical Biochemistry and Microbiology, Uppsala University, Sweden.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Heritable genome-wide variation of gene expression and promoter methylation between wild and domesticated chickens2012Ingår i: BMC Genomics, ISSN 1471-2164, E-ISSN 1471-2164, Vol. 13, nr 59Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Variations in gene expression, mediated by epigenetic mechanisms, may cause broad phenotypic effects in animals. However, it has been debated to what extent expression variation and epigenetic modifications, such as patterns of DNA methylation, are transferred across generations, and therefore it is uncertain what role epigenetic variation may play in adaptation. Here, we show that in Red Junglefowl, ancestor of domestic chickens, gene expression and methylation profiles in thalamus/hypothalamus differ substantially from that of a domesticated egg laying breed. Expression as well as methylation differences are largely maintained in the offspring, demonstrating reliable inheritance of epigenetic variation. Some of the inherited methylation differences are tissue-specific, and the differential methylation at specific loci are little changed after eight generations of intercrossing between Red Junglefowl and domesticated laying hens. There was an over-representation of differentially expressed and methylated genes in selective sweep regions associated with chicken domestication. Hence, our results show that epigenetic variation is inherited in chickens, and we suggest that selection of favourable epigenomes, either by selection of genotypes affecting epigenetic states, or by selection of methylation states which are inherited independently of sequence differences, may have been an important aspect of chicken domestication.

    Ladda ner fulltext (pdf)
    fulltext
  • 134.
    Nätt, Daniel
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Stranneheim, H.
    Lundeberg, Joakim
    School of Biotechnology, Department of Gene Technology, Royal Institute of Technology, Stockholm, Sweden.
    Torjesen, Peter A.
    Hormone Laboratory, Aker University Hospital HF, Oslo, Norway.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Transgenerational Phenotypic Tuning of Offspring: Adaptive Responses to a Prenatal Environmental Challenge in Chickens2008Manuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Stress may affect both the exposed individuals and the development of their offspring. We have previously shown that offspring of stressed domestic chickens can inherit the stressed-induced learning impairments of their parents and the associated modifications in brain gene expression. In this study we investigated possible adaptive aspects of such cross-generation transmissions. We hypothesized that stress would cause chickens to show a more conservative feeding strategy and to be more dominant, and that these adaptations would be transmitted to the offspring. Parents were raised in an unpredictable diurnal light rhythm (stress treatment) or in control conditions (12:12 h light:dark). In a foraging test, stressed birds pecked more at freely available than at hidden and more attractive food compared to birds from the control group. Female offspring of stressed birds, raised in control conditions without parental contact, showed a similar foraging behavior, differing from offspring of control birds. Furthermore, adult offspring of stressed birds performed more food pecks in a dominance test, showed a higher preference for high energy food, survived better, and were heavier than offspring of control parents. One possible explanation for the more dominant behavior of these birds might be increased androgen/estrogen effects from the yolk during their embryonic phase leading to increased anabolism and androgenic behavior. Using cDNA microarrays, we found that some of the differential brain gene expression caused by stress tended to be mirrored in the offspring, indicating transgenerational effects.  In particular, several immunoglobulin genes seemed to be affected similarly in both stressed parents and their offspring. Estradiol, but not corticoserone, testosterone, androstendion, or dihydrotestosterone, was significantly higher in egg yolk from stressed birds, suggesting a possible mechanism for these effects. Our findings suggest that stress may cause adaptive responses in feeding behavior, which may be transmitted to the offspring by means of epigenetic regulation of immune genes. This may in turn prepare the offspring for coping with an unpredictable environment.

  • 135.
    Olsson, Peter
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Laska, Matthias
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Human Male Superiority in Olfactory Sensitivity to the Sperm Attractant Odorant Bourgeonal2010Ingår i: Chemical Senses, ISSN 0379-864X, E-ISSN 1464-3553, Vol. 35, nr 5, s. 427-432Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Recent studies have shown that sperm chemotaxis critically involves the human olfactory receptor OR1D2, which is activated bythe aromatic aldehyde bourgeonal. Given that both natural and sexual selection may act upon the expression of receptors, wehypothesized that human males are more sensitive than human females for bourgeonal. Using a 3-alternative forced-choicetest procedure, olfactory detection thresholds were determined for a total of 500 subjects, 250 males, and 250 femalesbetween 18 and 40 years of age. We found that male subjects detected bourgeonal at significantly lower concentrations(mean value: 13 ppb) compared with female subjects (mean value: 26 ppb), whereas no such gender difference in olfactorysensitivity was found with helional, a structural analog of bourgeonal, and with n-pentyl acetate, an aliphatic ester, which weretested in parallel. Males and females did not differ in their frequency of specific anosmia for any of the 3 odorants. Thefrequency distributions of olfactory detection thresholds were monomodal with all 3 odorants in both genders. Olfactorydetection thresholds did not differ significantly between pre- and postovulatory females with any of the 3 odorants. To the bestof our knowledge, this is the first study ever to find a human male superiority in olfactory sensitivity. Single nucleotidepolymorphisms and/or copy number variations in genes coding for olfactory receptors may be the proximate cause for ourfinding, whereas a gender difference in the behavioral relevance of bourgeonal may be the ultimate cause.

  • 136.
    Olsson, Peter
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Laska, Matthias
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Human male superiority in olfactory sensitivity to the sperm-attractant odorant bourgeonal2010Konferensbidrag (Refereegranskat)
  • 137. Phillips, K.M.
    et al.
    Österman, H.K.
    Boman, E.
    Patel, H.K.
    Kim, D.H.
    Shepherd, G.M.
    Laska, Matthias
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Willhite, D.C.
    Olfactory performance in three transgenic Alzheimer's disease mouse model strains2010Konferensbidrag (Övrigt vetenskapligt)
  • 138.
    Phillips, Matthew
    et al.
    Department of Neurobiology, Yale University School of Medicine, New Haven, Connecticut.
    Boman, Erik
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Österman, Hanna
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Willhite, David
    Department of Neurobiology, Yale Univesity School of Medicine, New Haven, Connecticut.
    Laska, Matthias
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Olfactory and Visuospatial Learning and MemoryPerformance in Two Strains of Alzheimer’s DiseaseModel Mice—A Longitudinal Study2011Ingår i: PLoS ONE, ISSN 1932-6203, Vol. 6, nr 5, s. e19567-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Using a longitudinal study design, two strains of Alzheimer’s disease (AD) model mice, one expressing b-amyloid plaquesand one expressing Tau protein-associated neurofibrillary tangles were assessed for olfactory and visuospatial learning andmemory and their performance compared to that of age-matched controls. No significant difference between AD andcontrol mice was found in the initial set of olfactory tasks performed at 6 months of age whereas both strains of AD miceperformed significantly poorer than the controls in visuospatial learning at this age. Subsequent tests performed on thesame individual animals at 7, 8, 9, 11, 13, 15, and 18 months of age also failed to find systematic differences in olfactoryperformance between AD and control mice. In contrast, the AD mice performed consistently poorer than the controls invisuospatial re-learning tests performed at these ages. With most olfactory tasks, both AD and control mice displayed amarked decrease in performance between testing at 15 and 18 months of age. These results show that the two strains of ADmodel mice do not display an olfactory impairment in a time course consistent with human AD, but are impaired invisuospatial capabilities. The marked age-related changes observed with the olfactory tasks in both AD and control micesuggest that the observed lack of an AD-related olfactory impairment is not due to an insensitivity of the tests employed.Rather, they suggest that the olfactory system of the two AD mouse model strains may be surprisingly robust against ADtypicalneuropathologies.

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    fulltext
  • 139.
    Pizzari, T.
    et al.
    Section of Ethology, Dept. of Anim. Environ. and Health, Swed. Univ. of Agricultural Sciences, PO Box 234, Skara SE 532 31, Sweden, Evolution and Ecology Group, School of Biology, University of Leeds, Leeds LS2 9JT, United Kingdom.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi.
    Cornwallis, C.K.
    Dept. of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, United Kingdom.
    A novel test of the phenotype-linked fertility hypothesis reveals independent components of fertility2004Ingår i: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 271, nr 1534, s. 51-58Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The phenotype-linked fertility hypothesis predicts that male sexual ornaments signal fertilizing efficiency and that the coevolution of male ornaments and female preference for such ornaments is driven by female pursuit of fertility benefits. In addition, directional testicular asymmetry frequently observed in birds has been suggested to reflect fertilizing efficiency and to covary with ornament expression. However, the idea of a phenotypic relationship between male ornaments and fertilizing efficiency is often tested in populations where environmental effects mask the underlying genetic associations between ornaments and fertilizing efficiency implied by this idea. Here, we adopt a novel design, which increases genetic diversity through the crossing of two divergent populations while controlling for environmental effects, to test: (i) the phenotypic relationship between male ornaments and both, gonadal (testicular mass) and gametic (sperm quality) components of fertilizing efficiency, and (ii) the extent to which these components are phenotypically integrated in the fowl, Gallus gallus. We show that consistent with theory, the testosterone-dependent expression of a male ornament, the comb, predicted testicular mass. However, despite their functional inter-dependence, testicular mass and sperm quality were not phenotypically integrated. Consistent with this result, males of one parental population invested more in testicular and comb mass, whereas males of the other parental population had higher sperm quality. We found no evidence that directional testicular asymmetry covaried with ornament expression. These results shed new light on the evolutionary relationship between male fertilizing efficiency and ornaments. Although testosterone-dependent ornaments may covary with testicular mass and thus reflect sperm production rate, the lack of phenotypic integration between gonadal and gametic traits reveals that the expression of an ornament is unlikely to reflect the overall fertilizing efficiency of a male.

  • 140.
    Rashdan, Nabil
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi.
    The effects of prenatal hypoxia on the levels of the α-subunits of G proteins in the heart of the Broiler chicken (Gallus gallus)2010Självständigt arbete på avancerad nivå (masterexamen), 40 poäng / 60 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Environmental stress during embryonic development could lead to growth restriction of the embryo, and act as a risk factor for the development of cardiovascular disease in adult life. A common environmental stressor that causes growth restriction is prenatal hypoxia, which has been shown to adversely affect adult health in mammalian models. Prenatal hypoxia causes an increase in catecholamines which results in over stimulation of the cardiac β-adrenergic receptors. Previous work on chickens has shown that prenatal hypoxia causes an increase in the sensitivity of β-adrenergic receptors to epinephrine in the embryonic heart. The sensitivity of these receptors was found to be decreased in prenatal hypoxic juvenile. Prenatal hypoxia has no significant effect on the density of these receptors in neither the embryo nor the juvenile. The lack of change in receptor density implies that the effects of hypoxia are further down stream in the signalling cascade. The β2 adrenergic receptor can couple to both the stimulatory Gα subunit (Gsα) and the inhibitory Gα subunit (Giα). We hypothesized that prenatal hypoxia would cause an increase in the Gsα in the sensitized embryos, while increasing Giα in the desensitized juveniles. This study evaluated the relative levels of Gsα and Giα in the hypoxic chicken embryo, and in the prenatally hypoxic juvenile, Using western blotting. Hypoxia considerably increased Giα in the chicken embryo while having no effect on Gsα. In the prenatally hypoxic juvenile Gsα was significantly increased while no changes were found in Giα. This dissociation between the levels of Gα subunit and receptor sensitivity implies that that hypoxia affects the signaling cascade downstream of the Gα subunit.

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  • 141.
    Rizvanovic, Alisa
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska högskolan.
    Amundin, Mats
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska högskolan.
    Laska, Matthias
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Olfactory Discrimination Ability of Asian Elephants (Elephas maximus) forStructurally Related Odorants2013Ingår i: Chemical Senses, ISSN 0379-864X, E-ISSN 1464-3553, Vol. 38, nr 2, s. 107-118Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Using a food-rewarded two-choice instrumental conditioning paradigm, we assessed the ability of Asian elephants, Elephasmaximus, to discriminate between 2 sets of structurally related odorants. We found that the animals successfully discriminatedbetween all 12 odor pairs involving members of homologous series of aliphatic 1-alcohols, n-aldehydes, 2-ketones,and n-carboxylic acids even when the stimuli differed from each other by only 1 carbon. With all 4 chemical classes, the elephantsdisplayed a positive correlation between discrimination performance and structural similarity of odorants in terms ofdifferences in carbon chain length. The animals also successfully discriminated between all 12 enantiomeric odor pairs tested.An analysis of odor structure–activity relationships suggests that a combination of molecular structural properties rather thana single molecular feature may be responsible for the discriminability of enantiomers. Compared with other species testedpreviously on the same sets of odor pairs (or on subsets thereof), the Asian elephants performed at least as well as miceand clearly better than human subjects, squirrel monkeys, pigtail macaques, South African fur seals, and honeybees. Furthercomparisons suggest that neither the relative nor the absolute size of the olfactory bulbs appear to be reliable predictors ofbetween-species differences in olfactory discrimination capabilities. In contrast, we found a positive correlation between thenumber of functional olfactory receptor genes and the proportion of discriminable enantiomeric odor pairs. Taken together,the results of the present study support the notion that the sense of smell may play an important role in regulating thebehavior of Asian elephants.

  • 142.
    Rubin, Carl-Johan
    et al.
    Department of Medical Sciences Uppsala University.
    Lindberg, Johan
    Department of Gene Technology Royal Institute of Technology, Stockholm.
    Fitzsimmons, Carolyn
    Department of Animal Breeding and Genetics Swedish University of Agricultural Sciences, Uppsala.
    Savolainen, Peter
    Department of Gene Technology Royal Institute of Technology, Stockholm.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Lundeberg, Joakim
    Department of Gene Technology Royal Institute of Technology, Stockholm.
    Andersson, Leif
    Department of Animal Breeding and Genetics Swedish University of Agricultural Sciences, Uppsala.
    Kindmark, Andreas
    Department of Medical Sciences Uppsala University.
    Differential gene expression in femoral bone from red junglefowl and domestic chicken, differing for bone phenotypic traits2007Ingår i: BMC Genomics, ISSN 1471-2164, E-ISSN 1471-2164, Vol. 8Artikel i tidskrift (Refereegranskat)
  • 143.
    Rubin, Carl-Johan
    et al.
    Uppsala University.
    Zody, Michael C.
    Uppsala University, Broad Institute of Harvard.
    Meadows, Jennifer R. S.
    Uppsala University.
    Sherwood, Ellen
    Karolinska Institutet.
    Webster, Matthew
    Uppsala University.
    Jiang, Lin
    Uppsala University.
    Ingman, Max
    The Rudbeck Laboratory, Uppsala University.
    Sharpe, Ted
    Broad Institute of Harvard and MIT.
    Ka, Sojeong
    Department of Neurosceince, Uppsala University.
    Hallböök, Finn
    Department of Neurosceince, Uppsala University.
    Besnier, Francois
    Swedish University of Agricultural Sciences.
    Carlborg, Örjan
    Swedish University of Agricultural Sciences.
    Bed'hom, Bertrand
    INRA, AgroPArisTech.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Siegel, Paul
    Virginia Polytechnic Institute and State University.
    Lindblad-Toh, Kerstin
    Uppsala University, Broad Institute of Harvard and MIT.
    Andersson, Leif
    Uppsala University, Swedish University of Agricultural Sciences.
    Whole-genome resequencing reveals loci under selection during chicken domestication2010Ingår i: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 464, s. 587-591Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Domestic animals are excellent models for genetic studies of phenotypic evolution(1-3). They have evolved genetic adaptations to a new environment, the farm, and have been subjected to strong human-driven selection leading to remarkable phenotypic changes in morphology, physiology and behaviour. Identifying the genetic changes underlying these developments provides new insight into general mechanisms by which genetic variation shapes phenotypic diversity. Here we describe the use of massively parallel sequencing to identify selective sweeps of favourable alleles and candidate mutations that have had a prominent role in the domestication of chickens (Gallus gallus domesticus) and their subsequent specialization into broiler (meat-producing) and layer (egg-producing) chickens. We have generated 44.5-fold coverage of the chicken genome using pools of genomic DNA representing eight different populations of domestic chickens as well as red jungle fowl (Gallus gallus), the major wild ancestor(4). We report more than 7,000,000 single nucleotide polymorphisms, almost 1,300 deletions and a number of putative selective sweeps. One of the most striking selective sweeps found in all domestic chickens occurred at the locus for thyroid stimulating hormone receptor (TSHR), which has a pivotal role in metabolic regulation and photoperiod control of reproduction in vertebrates. Several of the selective sweeps detected in broilers overlapped genes associated with growth, appetite and metabolic regulation. We found little evidence that selection for loss-of-function mutations had a prominent role in chicken domestication, but we detected two deletions in coding sequences that we suggest are functionally important. This study has direct application to animal breeding and enhances the importance of the domestic chicken as a model organism for biomedical research.

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  • 144.
    Rubin, Carl-John
    et al.
    Department of Medical Sciences Uppsala University.
    Brändström, Helena
    Department of Medical Sceinces Uppsala University.
    Wright, Dominic
    Department of Medical Biochemistry and Microbiology Uppsala University.
    Kerje, Susanne
    Department of Medical Biochemistry and Microbiology Uppsala University.
    Gunnarsson, Ulrika
    Department of Medical Biochemistry and Microbiology Uppsala University.
    Schütz, Karin
    AgResearch Animal Behaviour and Welfare, New Zealand.
    Fredriksson, Robert
    Department of Neuroscience Uppsala University.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Andersson, Leif
    Department of Medical Biochemistry and Microbiology Uppsala University.
    Ohlsson, Claes
    Department of Internal Medicine The Sahlgrenska University Hospital, Göteborg.
    Mallmin, Hans
    Department of Surgical Sciences Uppsala University Hospital, Uppsala.
    Larsson, Sune
    Department of Surgical Sciences Uppsala University Hospital, Uppsala.
    Kindmark, Andreas
    Department of Medical Sciences Uppsala University.
    Quantitative trait loci for BMD and bone strength in an intercross between domestic and wildtype chickens2007Ingår i: Journal of Bone and Mineral Research, ISSN 0884-0431, E-ISSN 1523-4681, Vol. 22, nr 3, s. 375-384Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    With chicken used as a model species, we used QTL analysis to examine the genetic contribution to bone traits. We report the identification of four QTLs for femoral traits: one for bone strength, one for endosteal circumference, and two affecting mineral density of noncortical bone. INTRODUCTION: BMD is a highly heritable phenotype, governed by elements at numerous loci. In studies examining the genetic contribution to bone traits, many loci have been identified in humans and in other species. The goal of this study was to identify quantitative trait loci (QTLs) controlling BMD and bone strength in an intercross between wildtype and domestic chickens. MATERIALS AND METHODS: A set of 164 markers, covering 30 chromosomes (chr.), were used to genotype 337 F2-individuals from an intercross of domesticated white Leghorn and wildtype red junglefowl chicken. DXA and pQCT were used to measure BMD and bone structure. Three-point bending tests and torsional strength tests were performed to determine the biomechanical strength of the bone. QTLs were mapped using forward selection for loci with significant marginal effects. RESULTS: Four QTLs for femoral bone traits were identified in QTL analysis with body weight included as a covariate. A QTL on chr. 1 affected female noncortical BMD (LOD 4.6) and is syntenic to human 12q21-12q23. Also located on chr. 1, a locus with synteny to human 12q13-14 affected endosteal circumference (LOD 4.6). On chr. 2, a QTL corresponding to human 5p13-p15, 7p12, 18q12, 18q21, and 9q22-9q31 affected BMD in females; noncortical (LOD 4.0) and metaphyseal (LOD 7.0) BMD by pQCT and BMD by DXA (LOD 5.9). A QTL located on chr. 20 (LOD 5.2) affected bone biomechanical strength and had sex-dependent effects. In addition to the significant QTLs, 10 further loci with suggestive linkage to bone traits were identified. CONCLUSIONS: Four QTLs were identified: two for noncortical BMD, one for endosteal circumference, and one affecting bone biomechanical strength. The future identification of genes responsible for these QTLs will increase the understanding of vertebrate skeletal biology.   

  • 145.
    Rydmell, Sara
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi.
    The honesty of the female sexual ornament in Gallus gallus2010Självständigt arbete på avancerad nivå (masterexamen), 40 poäng / 60 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Sexual selection was defined by Darwin in 1871 as selection acting solely on reproduction success. It is known to act on males resulting in extravagant ornamentations or other attributes, but in recent years more studies have shown that sexual selection also act on females. There is empirical evidence in several taxa that the secondary sexual ornament also acts as a measurement on the females’ reproductive quality, it is an honest trait. In Gallus gallus the comb has been found to be an honest ornament. Quantitative Trait Loci have been found on chromosome 1 and 3 for comb- and egg size. The honesty of the comb is hypothesized to be caused by either a pleiotropic effect gene linkage. In this study an 8th generation Advanced Interline Cross was used to guarantee maximum recombination of alleles to observe phenotypic effects. 177 females were detained during 4 weeks to measure fecundity. Egg number, mean egg weight and total egg size were correlated to comb size: length, area and weight. Correlation between comb size and total egg weight were found to be negative, suggesting the comb to be a dishonest signal. The phenotypic measurements observed in this study suggest that the genes for egg production and comb size are linked, and this linkage has been broken in the F8 analysed in this study.

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  • 146.
    Sandbom, Erik
    et al.
    Department of Zoology, Göteborg University.
    Farrell, Anthony P
    University of British Columbia, Canada.
    Altimiras, Jordi
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Axelsson, Michael
    Department of Zoology, Göteborg University.
    Claireau, Guy
    Place du Séminaire, L'Houmeau, France .
    Cardiac preload and venous return in swimming sea bass (Dicentrarchus labrax L.)2005Ingår i: Journal of Experimental Biology, ISSN 0022-0949, E-ISSN 1477-9145, Vol. 208, s. 1927-1935Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Cardiac preload (central venous pressure, P(CV), mean circulatory filling pressure (MCFP), dorsal aortic blood pressure (P(DA)) and relative cardiac output (Q) were measured in sea bass (Dicentrarchus labrax) at rest and while swimming at 1 and 2 BL s(-1). MCFP, an index of venous capacitance and the upstream venous pressure driving the return of venous blood to the heart, was measured as the plateau in Pcv during ventral aortic occlusion. Compared with resting values, swimming at 1 and 2 BL s(-1) increased Q (by 15+/-1.5 and 38+/-6.5%, respectively), P(CV) (from 0.11+/-0.01 kPa to 0.12+/-0.01 and 0.16+/-0.02 kPa, respectively), MCFP (from 0.27+/-0.02 kPa to 0.31+/-0.02 and 0.40+/-0.04 kPa, respectively) and the calculated pressure gradient for venous return (DeltaP(V), from 0.16+/-0.01 kPa to 0.18+/-0.02 and 0.24+/-0.02 kPa, respectively), but not P(DA). In spite of an increased preload, the increase in Q was exclusively mediated by an increased heart rate (f(H), from 80+/-4 beats min(-1) to 88+/-4 and 103+/-3 beats min(-1), respectively), and stroke volume (Vs) remained unchanged. Prazosin treatment (1 mg kg(-1) Mb) abolished pressure and flow changes during swimming at 1 BL s(-1), but not 2 BL s(-1), indicating that other control systems besides an alpha-adrenoceptor control are involved. This study is the first to address the control of venous capacitance in swimming fish. It questions the generality that increased Q during swimming is regulated primarily through Vs and shows that an increased cardiac filling pressure does not necessarily lead to an increased Vs in fish, but may instead compensate for a reduced cardiac filling time.

  • 147.
    Sarrafchi, Amir
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska högskolan.
    Odhammer, Anna M.E.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska högskolan.
    Hernandez Salazar, Laura Teresa
    Instituto de Neuro-Etologia, Universidad Veracruzana, Xalapa, Veracruz, Mexico.
    Laska, Matthias
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Olfactory Sensitivity for Six Predator Odorants in CD-1Mice, Human Subjects, and Spider Monkeys2013Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 8, nr 11, s. e80621-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Using a conditioning paradigm, we assessed the olfactory sensitivity of six CD-1 mice (Mus musculus) for six sulfurcontainingodorants known to be components of the odors of natural predators of the mouse. With all six odorants, themice discriminated concentrations ,0.1 ppm (parts per million) from the solvent, and with five of the six odorants the bestscoringanimals were even able to detect concentrations ,1 ppt (parts per trillion). Four female spider monkeys (Atelesgeoffroyi) and twelve human subjects (Homo sapiens) tested in parallel were found to detect the same six odorants atconcentrations ,0.01 ppm, and with four of the six odorants the best-scoring animals and subjects even detectedconcentrations ,10 ppt. With all three species, the threshold values obtained here are generally lower than (or in the lowerrange of) those reported for other chemical classes tested previously, suggesting that sulfur-containing odorants may play aspecial role in olfaction. Across-species comparisons showed that the mice were significantly more sensitive than the humansubjects and the spider monkeys with four of the six predator odorants. However, the human subjects were significantlymore sensitive than the mice with the remaining two odorants. Human subjects and spider monkeys significantly differed intheir sensitivity with only two of the six odorants. These comparisons lend further support to the notion that the number offunctional olfactory receptor genes or the relative or absolute size of the olfactory bulbs are poor predictors of a species’olfactory sensitivity. Analysis of odor structure–activity relationships showed that in both mice and human subjects the typeof alkyl rest attached to a thietane and the type of oxygen moiety attached to a thiol significantly affected olfactorysensitivity.

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  • 148. Schutz, KE
    et al.
    Kerje, Susanne
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi.
    Jacobsson, L
    Forkman, B
    Carlborg, O
    Andersson, L
    Jensen, Per
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi.
    Major growth QTLs in fowl are related to fearful behavior: possible genetic links between fear responses and production traits in a red junglefowl x White Leghorn intercross2004Ingår i: Behavior Genetics, ISSN 0001-8244, E-ISSN 1573-3297, Vol. 34, nr 1, s. 121-130Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aim of this work was to study fear responses and their relation to production traits in red junglefowl (Gallus gallus spp.), White Leghorn (Gallus domesticus), and their F-2-progeny. Quantitative trait locus (QTL) analyses were performed for behavioral traits to gain information about possible genetic links between fear-related behaviors and production. Four behavioral tests were performed that induce different levels of acute fear (open field [OF], exposure to a novel object, tonic immobility, and restraint). Production traits, that is, egg production, sexual maturity (in females), food intake, and growth, were measured individually. A genome scan using 105 microsatellite markers was carried out to identify QTLs controlling the traits studied. In the OF and novel object tests (NO), Leghorns showed less fear behavior than junglefowl, whereas junglefowl behaved less fearfully in the tonic immobility test (TI) and were more active in the restraint test. In the F-2 progeny, only weak phenotypic associations were found between production traits and fear behavior. A significant QTL for TI duration was found on chromosome 1 that coincided with a QTL for egg weight and growth in the same animals. Another QTL for NO in males coincided with another major growth QTL. These two known growth QTLs affected a wide range of reactions in different tests. Several other significant and suggestive QTLs for behavioral traits related to fear were found. These QTLs did not coincide with QTLs for production traits, indicating that these fear variables may not be genetically linked to the production traits we measured here. The results show that loci affecting important production traits are located in the same chromosomal region as loci affecting different fear-related behaviors.

  • 149.
    Sjölander, Sverre
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi.
    Singing birds, playing cats, and babbling babies: Why do they do it?2000Ingår i: Phonetica, ISSN 0031-8388, E-ISSN 1423-0321, Vol. 57, nr 2-4, s. 197-204Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Rarely, animals do what they do because they are aware of the function of the behaviour or its outcome. Instead, they will very often perform behaviour out of context, spontaneously, as play. The impression (strengthened by introspection in the human species) is that they do it because they get some kind of internal reward. Nevertheless, such seemingly meaningless behaviour may have an ultimate function to adjust behavioural programs to the body, to practice, to perfect the execution of the behaviour. If the proximate reason for doing what the animal does may be to attain a pleasurable state, the ultimate, evolutionary reason may still be that increased practice will give some gain in fitness. If one presupposes internal rewarding and punishing systems as intervening factors, it becomes much simpler to explain why birds sing, kittens play or babies babble without any outer reward and out of any functional context, more than needed from a strictly functional view, spontaneously and just for the fun of it, copyright (C) 2000 S. Karger AG, Basel.

  • 150.
    Starkhammar, Josefin
    et al.
    Lund University, Lund, Sweden.
    Amundin, Mats
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Nilsson, Johan
    Lund University, Lund, Sweden.
    Jansson, Tomas
    Lund University, Lund, Sweden.
    Kuczaj, Stan A
    University of South Mississippi, Hattiesburg, MS, USA.
    Almqvist, Monica
    Lund University, Lund, Sweden.
    Persson, Hans W
    Lund University, Lund, Sweden.
    Editorial: 47-channel burst-mode recording hydrophone system enabling measurements of the dynamic echolocation behavior of free-swimming dolphins2009Ingår i: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 126, nr 3, s. 959-962Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    Detailed echolocation behavior studies on free-swimming dolphins require a measurement system that incorporates multiple hydrophones (often andgt; 16). However, the high data flow rate of previous systems has limited their usefulness since only minute long recordings have been manageable. To address this problem, this report describes a 47-channel burst-mode recording hydrophone system that enables highly resolved full beamwidth measurements on multiple free-swimming dolphins during prolonged recording periods. The system facilitates a wide range of biosonar studies since it eliminates the need to restrict the movement of animals in order to study the fine details of their sonar beams.

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