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  • 1.
    Abbey-Lee, Robin
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten. Max Planck Inst Ornithol, Germany.
    Araya-Ajoy, Yimen G.
    Norwegian Univ Sci and Technol, Norway.
    Mouchet, Alexia
    Max Planck Inst Ornithol, Germany.
    Moiron, Maria
    Max Planck Inst Ornithol, Germany.
    Stuber, Erica F.
    Univ Nebraska Lincoln, NE USA.
    Kempenaers, Bart
    Max Planck Inst Ornithol, Germany.
    Dingemanse, Niels J.
    Max Planck Inst Ornithol, Germany; Ludwig Maximilians Univ Munchen, Germany.
    Does perceived predation risk affect patterns of extra-pair paternity? A field experiment in a passerine bird2018Ingår i: Functional Ecology, ISSN 0269-8463, E-ISSN 1365-2435, Vol. 32, nr 4, s. 1001-1010Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Non-consumptive predator effects have been shown to influence a wide range of behavioural, life history and morphological traits. Extra-pair reproduction is widespread among socially monogamous birds and may incur predation costs. Consequently, altered rates of extra-pair reproduction are expected in circumstances characterized by increased adult perceived predation risk. In addition, extra-pair reproduction is expected to be most affected for birds with phenotypes that generally increase predation risk (such as more active individuals). In two consecutive years, perceived predation risk was manipulated for great tits Parus major breeding in 12 nest-box plots by broadcasting sounds of their main predator (European sparrowhawk Accipiter nisus; six plots). As a control treatment, sounds of a sympatric, avian non-predator species were broadcast (Eurasian blackbird Turdus merula; six plots). Levels of extra-pair paternity did not differ between plots with different predation risk treatments. Males that moved more in a novel environment (more active or faster exploring) tended to have offspring with fewer partners, but this effect did not vary with predation risk treatment. From an adaptive viewpoint, predation costs associated with extra-pair reproduction may be small and may not outweigh the benefits of extra-pair behaviour. Research on a broader range of taxa with different mating strategies is now needed to confirm the generality of our findings.

  • 2.
    Agnvall, Beatrix
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Bélteky, Johan
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Brain size is reduced by selectionfor tameness in Red Junglefowl–correlated effects in vital organs2017Ingår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, artikel-id 3306Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    During domestication animals have undergone changes in size of brain and other vital organs. We hypothesize that this could be a correlated effect to increased tameness. Red Junglefowl (ancestors of domestic chickens) were selected for divergent levels of fear of humans for five generations. The parental (P0) and the fifth selected generation (S5) were culled when 48–54 weeks old and the brains were weighed before being divided into telencephalon, cerebellum, mid brain and optic lobes. Each single brain part as well as the liver, spleen, heart and testicles were also weighed. Brains of S5 birds with high fear scores (S5 high) were heavier both in absolute terms and when corrected for body weight. The relative weight of telencephalon (% of brain weight) was significantly higher in S5 high and relative weight of cerebellum was lower. Heart, liver, testes and spleen were all relatively heavier (% of body weight) in S5 high. Hence, selection for tameness has changed the size of the brain and other vital organs in this population and may have driven the domesticated phenotype as a correlated response.

  • 3.
    Agnvall, Beatrix
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Katajamaa, Rebecca
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi.
    Altimiras, Jordi
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Is domestication driven by reduced fear of humans? Boldness, metabolism and serotonin levels in divergently selected red junglefowl (Gallus gallus)2015Ingår i: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 11, nr 9, artikel-id 20150509Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Domesticated animals tend to develop a coherent set of phenotypic traits. Tameness could be a central underlying factor driving this, and we therefore selected red junglefowl, ancestors of all domestic chickens, for high or low fear of humans during six generations. We measured basal metabolic rate (BMR), feed efficiency, boldness in a novel object (NO) test, corticosterone reactivity and basal serotonin levels (related to fearfulness) in birds from the fifth and sixth generation of the high- and low-fear lines, respectively (44-48 individuals). Corticosterone response to physical restraint did not differ between selection lines. However, BMR was higher in low-fear birds, as was feed efficiency. Low-fear males had higher plasma levels of serotonin and both low-fear males and females were bolder in an NO test. The results show that many aspects of the domesticated phenotype may have developed as correlated responses to reduced fear of humans, an essential trait for successful domestication.

  • 4.
    Altimiras, Jordi
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Lindgren, Isa
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Giraldo-Deck, Lina Maria
    University of Mayor San Andres, Bolivia.
    Matthei, Alberto
    Tinamou Chile SL, Chile.
    Garitano-Zavala, Alvaro
    University of Mayor San Andres, Bolivia.
    Aerobic performance in tinamous is limited by their small heart. A novel hypothesis in the evolution of avian flight2017Ingår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, artikel-id 15964Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Some biomechanical studies from fossil specimens suggest that sustained flapping flight of birds could have appeared in their Mesozoic ancestors. We challenge this idea because a suitable musculoskeletal anatomy is not the only requirement for sustained flapping flight. We propose the "heart to fly" hypothesis that states that sustained flapping flight in modern birds required an enlargement of the heart for the aerobic performance of the flight muscles and test it experimentally by studying tinamous, the living birds with the smallest hearts. The small ventricular size of tinamous reduces cardiac output without limiting perfusion pressures, but when challenged to fly, the heart is unable to support aerobic metabolism (quick exhaustion, larger lactates and post-exercise oxygen consumption and compromised thermoregulation). At the same time, cardiac growth shows a crocodilian-like pattern and is correlated with differential gene expression in MAPK kinases. We integrate this physiological evidence in a new evolutionary scenario in which the ground-up, short and not sustained flapping flight displayed by tinamous represents an intermediate step in the evolution of the aerobic sustained flapping flight of modern birds.

  • 5.
    Ananthakrishnan, Gopal
    et al.
    Centre for Speech Technology, KTH, Stockholm, Sweden.
    Eklund, Robert
    Linköpings universitet, Institutionen för datavetenskap, NLPLAB - Laboratoriet för databehandling av naturligt språk. Linköpings universitet, Tekniska högskolan.
    Peters, Gustav
    Forschungsinstitut Alexander Koenig, Bonn, Germany.
    Mabiza, Evans
    Antelope Park, Gweru, Zimbabwe.
    An acoustic analysis of lion roars. II: Vocal tract characteristics2011Ingår i: Proceedings from Fonetik 2011, Quarterly Progress and Status Report TMH-QPSR, Volume 51, 2011, 2011, s. 5-8Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    This paper makes the first attempt to perform an acoustic-to-articulatory inversion of a lion (Panthera leo) roar. The main problems that one encounters in attempting this, is the fact that little is known about the dimensions of the vocal tract, other than a general range of vocal tract lengths. Precious little is also known about the articulation strategies that are adopted by the lion while roaring. The approach used here is to iterate between possible values of vocal tract lengths and vocal tract configurations. Since there seems to be a distinct articulatory changes during the process of a roar, we find a smooth path that minimizes the error function between a recorded roar and the simulated roar using a variable length articulatory model.

  • 6.
    Arshamian, Artin
    et al.
    Karolinska Institute, Sweden; Radboud University of Nijmegen, Netherlands; Radboud University of Nijmegen, Netherlands; Stockholm University, Sweden.
    Laska, Matthias
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Gordon, Amy R.
    Karolinska Institute, Sweden; Monell Chemistry Senses Centre, PA 19104 USA.
    Norberg, Matilda
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska fakulteten.
    Lahger, Christian
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska fakulteten.
    Porada, Danja K.
    Karolinska Institute, Sweden.
    Jelvez Serra, Nadia
    Lund University, Sweden.
    Johansson, Emilia
    Karolinska Institute, Sweden.
    Schaefer, Martin
    Karolinska Institute, Sweden.
    Amundin, Mats
    Kolmarden Wildlife Pk, Sweden.
    Melin, Harald
    Karolinska Institute, Sweden.
    Olsson, Andreas
    Karolinska Institute, Sweden.
    Olsson, Mats J.
    Karolinska Institute, Sweden.
    Stensmyr, Marcus
    Lund University, Sweden.
    Lundstrom, Johan N.
    Karolinska Institute, Sweden; Monell Chemistry Senses Centre, PA 19104 USA; University of Penn, PA 19104 USA.
    A mammalian blood odor component serves as an approach-avoidance cue across phylum border - from flies to humans2017Ingår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, artikel-id 13635Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Chemosignals are used by predators to localize prey and by prey to avoid predators. These cues vary between species, but the odor of blood seems to be an exception and suggests the presence of an evolutionarily conserved chemosensory cue within the blood odor mixture. A blood odor component, E2D, has been shown to trigger approach responses identical to those triggered by the full blood odor in mammalian carnivores and as such, is a key candidate as a food/alarm cue in blood. Using a multidisciplinary approach, we demonstrate that E2D holds the dual function of affecting both approach and avoidance behavior in a predator-prey predicted manner. E2D evokes approach responses in two taxonomically distant blood-seeking predators, Stable fly and Wolf, while evoking avoidance responses in the prey species Mouse. We extend this by demonstrating that this chemical cue is preserved in humans as well; E2D induces postural avoidance, increases physiological arousal, and enhances visual perception of affective stimuli. This is the first demonstration of a single chemical cue with the dual function of guiding both approach and avoidance in a predator-prey predicted manner across taxonomically distant species, as well as the first known chemosignal that affects both human and non-human animals alike.

  • 7.
    Bianco, Giuseppe
    et al.
    Lund University, Sweden.
    Ilieva, Mihaela
    Lund University, Sweden; Bulgarian Academic Science, Bulgaria.
    Veibäck, Clas
    Linköpings universitet, Institutionen för systemteknik, Reglerteknik. Linköpings universitet, Tekniska fakulteten.
    Öfjäll, Kristoffer
    Linköpings universitet, Institutionen för systemteknik, Datorseende. Linköpings universitet, Tekniska fakulteten.
    Gadomska, Alicja
    Lund University, Sweden.
    Hendeby, Gustaf
    Linköpings universitet, Institutionen för systemteknik, Reglerteknik. Linköpings universitet, Tekniska fakulteten.
    Felsberg, Michael
    Linköpings universitet, Institutionen för systemteknik, Datorseende. Linköpings universitet, Tekniska fakulteten.
    Gustafsson, Fredrik
    Linköpings universitet, Institutionen för systemteknik, Reglerteknik. Linköpings universitet, Tekniska fakulteten.
    Åkesson, Susanne
    Lund University, Sweden.
    Emlen funnel experiments revisited: methods update for studying compass orientation in songbirds2016Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 6, nr 19, s. 6930-6942Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    1 Migratory songbirds carry an inherited capacity to migrate several thousand kilometers each year crossing continental landmasses and barriers between distant breeding sites and wintering areas. How individual songbirds manage with extreme precision to find their way is still largely unknown. The functional characteristics of biological compasses used by songbird migrants has mainly been investigated by recording the birds directed migratory activity in circular cages, so-called Emlen funnels. This method is 50 years old and has not received major updates over the past decades. The aim of this work was to compare the results from newly developed digital methods with the established manual methods to evaluate songbird migratory activity and orientation in circular cages. 2 We performed orientation experiments using the European robin (Erithacus rubecula) using modified Emlen funnels equipped with thermal paper and simultaneously recorded the songbird movements from above. We evaluated and compared the results obtained with five different methods. Two methods have been commonly used in songbirds orientation experiments; the other three methods were developed for this study and were based either on evaluation of the thermal paper using automated image analysis, or on the analysis of videos recorded during the experiment. 3 The methods used to evaluate scratches produced by the claws of birds on the thermal papers presented some differences compared with the video analyses. These differences were caused mainly by differences in scatter, as any movement of the bird along the sloping walls of the funnel was recorded on the thermal paper, whereas video evaluations allowed us to detect single takeoff attempts by the birds and to consider only this behavior in the orientation analyses. Using computer vision, we were also able to identify and separately evaluate different behaviors that were impossible to record by the thermal paper. 4 The traditional Emlen funnel is still the most used method to investigate compass orientation in songbirds under controlled conditions. However, new numerical image analysis techniques provide a much higher level of detail of songbirds migratory behavior and will provide an increasing number of possibilities to evaluate and quantify specific behaviors as new algorithms will be developed.

  • 8.
    Bouwman, Henk
    et al.
    Nort-West University, South Africa.
    Krátká, M
    Masaryk University, Czech Republic.
    Choong Kwet Yive, Nee Sun
    University of Mauritius, Mauritius.
    Kylin, Henrik
    Linköpings universitet, Institutionen för tema, Tema vatten i natur och samhälle. Linköpings universitet, Filosofiska fakulteten.
    Klanova, Jana
    Masaryk University, Czech Republic.
    Do POPs Transfer from Plastic Marine Debris to Coral on Tropical Islands?2014Ingår i: Organohalogen Compounds, ISSN 1026-4892, Vol. 76, s. 1352-1355Artikel i tidskrift (Refereegranskat)
  • 9.
    Edenborg, Fanny
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi.
    Artificial light at night causes advanced initiation of dawn song in songbirds in Linköping, Sweden2018Självständigt arbete på grundnivå (kandidatexamen), 10,5 poäng / 16 hpStudentuppsats (Examensarbete)
    Abstract [en]

    It is known that artificial light at night has a role in disrupting many birds’ routines when it comes to timing of dawn song. However, studies show various results on which species that are affected, how much and on what latitude. Birds at northern latitudes is experiencing longer and brighter natural nights during the breeding season as the spring is progressing, compared to birds living in areas more south. The bright nights might affect how the birds respond to the artificial light at night. This study's aim was to investigate how different species of songbirds in Linköping (58°N), Sweden, time their dawn song during breeding season, depending on presence or absence of artificial light at night coming from street lamps. The results show that early singing species are more affected than late singing species. The common blackbird for example, advanced its song because of artificial light, up to over an hour on average. Late singing birds was also affected by the urban lights, though not as strongly as the early singing species. Also shown was that the temperature and the amount of cloudiness, did not affect the difference in timing of dawn song between the locations. Future studies should focus on collecting data from more northern latitudes. The effect the advanced timing of dawn song, both regarding the birds on an individual scale and also regarding the ecosystems in total,should also be investigated further.

  • 10.
    Eklund, Robert
    et al.
    Voice Provider, Stockholm, Sweden .
    Peters, Gustav
    Forschungsinstitut Alexander Koenig, Bonn, Germany.
    Ananthakrishnan, Gopal
    Centre for Speech Technology, Royal Institute of Technology, Stockholm, Sweden.
    Mabiza, Evans
    Antelope Park, Gweru, Zimbabwe.
    An acoustic analysis of lion roars. I: Data collection and spectrogramand waveform analyses2011Ingår i: Quarterly Progress and Status Report TMH-QPSR, Volume 51, 2011. Proceedings from Fonetik 2011. Royal Institute of Technology, Stockholm, Sweden, 8–10 June 2011, pp. 1–4., Stockholm: Universitetsservice , 2011, s. 1-4Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    This paper describes the collection of lion roar data at two different locations, anoutdoor setting at Antelope Park in Zimbabwe and an indoor setting at Parken Zooin Sweden. Preliminary analyses of spectrographic and waveform data are provided.

  • 11.
    Eklund, Robert
    et al.
    Karolinska Institute / Stockholm Brain Institute, Stockholm, Sweden / Voice Provider Sweden, Stockholm, Sweden / Linköping University, Linköping, Sweden.
    Peters, Gustav
    Forschungsmuseum Alexander Koenig, Bonn, Germany.
    Duthie, Elizabeth D.
    Dell Cheetah Centre, Parys, South Africa.
    An acoustic analysis of purring in the cheetah (Acinonyx jubatus) and in the domestic cat (Felis catus)2010Ingår i: Proceedings of Fonetik 2010, Lund, Sweden: Mediatryck , 2010, s. 17-22Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    This paper analyses purring in a cheetah and a domestic cat from an acoustic point of view.

    The results are discussed in the light of previously published studies.

  • 12.
    Eklund, Robert
    et al.
    Linköpings universitet, Institutionen för kultur och kommunikation, Avdelningen för språk och kultur. Linköpings universitet, Filosofiska fakulteten.
    Peters, Gustav
    Forschungsmuseum Alexander Koenig, Bonn, Germany.
    Weise, Florian
    N/a’an ku sê Foundation, Windhoek, Namibia.
    Munro, Stuart
    N/a’an ku sê Foundation, Windhoek, Namibia.
    A comparative acoustic analysis of purring in four cheetahs2012Ingår i: Proceedings from FONETIK 2012 / [ed] Åsa Abelin and Anders Eriksson, Gothenburg: University of Gothenburg , 2012, s. 41-44Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    This paper reports results from a comparativeanalysis of purring in four tame cheetahs. Theresults exhibited individual variation forrelative phase duration and number of cyclesper phase, while egressive phases were louderand had higher fundamental frequency in allfour cheetahs.

  • 13.
    Elfwing, Magnus
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska högskolan.
    The Physiology of Chicken Domestication: Involvement of the HPA-axis and the Autonomic Nervous System2015Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Domesticering är en urvalsprocess för önskvärda egenskaper hos djur som över tid förändrar deras utseende, beteende och genetik. Några exempel av djur som genomgått denna riktade avel är vargen, mufflon, uroxen, vildsvinet och den röda djungelhönan som vi idag känner som hunden, fåret, kon, grisen och slaktkycklingen.

    Några gemensamma egenskaper hos domesticerade djur är minskad rädsla för människor, och att de troligen har en högre stresstolerans jämfört med sina vilda förfäder. Det finns två huvudsakliga fysiologiska mekanismer som styr dessa responser, en hormonell och en nervös. Nervsystemet är i sin tur uppdelat i sympatiska och parasympatiska nervsystemet vilka har motsatta roller för kroppens funktioner. Under stress ger det sympatiska den så kallade ”Fight-and-flight”-responsen, och det parasympatiska aktiveras under vila och kallas ”rest-and-digest”-systemet. Det verkar troligt att domesticeringen agerat på dessa system för att minska rädsla och stress hos våra tamdjur.

    Den här avhandlingen studerar stressresponser hos höns. Dessa används i stor skala inom livsmedelsindustrin, slaktkycklingen för köttproduktion samt värphöns för äggproduktion. De har avlats hårt för snabb tillväxt och hög äggproduktion. En slaktkyckling ökar sin vikt till 50 gånger kläckvikten på sex veckor! Det sympatiska nervsystemet, samt stresshormoner, agerar för nedbrytande och energifrisläppande mekanismer, och det parasympatiska samt låg stress verkar för uppbyggande och energisparande mekanismer. Därför bör avel på låg stress och låg sympatisk aktivitet vara fördelaktigt för hög tillväxt.

    Experimenten i avhandlingen undersöker utvecklingen och mognaden av det autonoma nervsystemet hos kycklingar, domesticeringseffekter samt om stress tidigt i livet påverkar höns som vuxna. Vi fann att kycklingfoster redan vid 75 % av fosterutvecklingen har en funktionell parasympatisk stimulering på hjärtat och att dess inverkan ökar närmare kläckningen. Efter kläckning styrs hjärtat i huvudsak av det sympatiska nervsystemet och först vid ca 5 veckors ålder tycks systemet närma sig mognad. Vi hittade också domesticeringseffekter på hjärtfrekvensen, som styrs av det autonoma nervsystemet, hos framför allt slaktkycklingar som har en lägre hjärtfrekvens jämfört med djungelhönan.

    Tidigare studier har indikerat att en gen som uttrycker ett protein i hjärnan, i sympatiska nervsystemet samt i binjurarna har varit viktig för aveln på våra tamhöns. Denna gen, ADRA2C, styr till exempel frisläppningen av stresshormon från binjurarna. Vi undersökte eventuella domesticeringseffekter på denna gen med avseende på genuttryck, proteinmängd, beteenden, tillväxt samt äggproduktion, men trots att starka indikationer på att genen borde ha viktiga effekter, hittade vi inget stöd för att det.

    Det är inte enbart domesticering som kan ha inverkan på stress. Erfarenheter tidigt i livet kan förändra individens välmående som vuxen och även ha effekter på dess avkomma. Vi undersökte dessa aspekter hos höns som avlats för äggläggning genom att stressa dem under de första veckorna efter kläckning och följde dem till vuxen ålder. Fåglarna uppvisade livslång påverkan av sina erfarenheter och framför allt hanar var särskilt känsliga och fick långsiktiga förändringar i beteendet, försenad hormonfrisättning vid puberteten och förändrad genuttrycksprofil i hypotalamus. Dessa modifieringar kan vara ett resultat av att aveln riktat sig i huvudsak mot honor för deras äggläggningsförmåga, och att hanar därmed ej blivit lika motståndskraftiga mot stress tidigt i livet. Även hanar i avkomman påverkades av föräldrarnas tidiga erfarenheter. De hade förändrat beteende, ändrad hormonell stressrespons och förändrat genuttryck.

    Sammantaget visar resultaten hur nervsystemet utvecklas hos höns, samt att nervsystemet förändrats av den moderna aveln. Vidare kunde vi visa att stress tidigt i livet hos höns kan få långsiktiga effekter som involverar stressresponsen vilket kan få konsekvenser för djurets välfärd.

    Delarbeten
    1. Fetal development of baroreflex sensitivity: The chicken embryo as a case model
    Öppna denna publikation i ny flik eller fönster >>Fetal development of baroreflex sensitivity: The chicken embryo as a case model
    2011 (Engelska)Ingår i: Respiratory Physiology & Neurobiology, ISSN 1569-9048, E-ISSN 1878-1519, Vol. 178, nr 1, s. 75-83Artikel, forskningsöversikt (Refereegranskat) Published
    Abstract [en]

    The baroreflex is the main short term compensatory mechanism to buffer blood pressure changes and maintain circulatory homeostasis. Its ontogeny and importance during prenatal life is not fully understood so we used broiler chickens to investigate the maturation of the baroreflex in late incubation using a novel method that measured changes in heart rate during spontaneous fluctuations in blood pressure. Our results suggest that a baroreflex is already functional at d17 with no indication of further maturation in terms of sensitivity (gain at 17 d was 52.9 ± 8.3 and at 20 d 69.5 ± 16.2 ms kPa−1). The physiological relevance of these values is shown using data surrogation methods. Although the results contrast with the progressive baroreflex maturation indicated by the pharmacological method, we sustain that both methods provide information on baroreflex regulation. While the spontaneous method evaluates truly physiological (but small) pressure changes, the pharmacological method provides a more consistent and repetitive challenge for the reflex that requires a different recruitment of baroreflex effectors.

    Ort, förlag, år, upplaga, sidor
    Elsevier B.V., 2011
    Nyckelord
    Baroreflex sensitivity, Spontaneous baroreflex, Cardiovascular development, Sodium nitroprusside
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-70254 (URN)10.1016/j.resp.2011.03.031 (DOI)000294098200010 ()
    Anmärkning
    Funding Agency|Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning (FORMAS)||Swedish Research Council for Natural Sciences (VR-NT)||University of Linkoping||Wallenberg Foundation||Tillgänglig från: 2011-08-29 Skapad: 2011-08-29 Senast uppdaterad: 2017-12-08
    2. The maturation of heart rate control in the Red Junglefowl (Gallus gallus)
    Öppna denna publikation i ny flik eller fönster >>The maturation of heart rate control in the Red Junglefowl (Gallus gallus)
    2015 (Engelska)Manuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Fetal development of autonomic cardiac control has been thoroughly investigated in chickens, but the maturation of the autonomic nervous system after hatching has gained little attention. At hatch the heart is under a feeble nervous control and there are indications suggesting a rapid maturation process during the first two weeks of postnatal life. We aimed to characterize the maturation by measuring heart rate at baseline and stressful conditions during the first 5 weeks of life in the Red Junglefowl and using autonomic antagonists to quantify the contribution of sympathetic and parasympathetic activity. We also compared the Red Junglefowl to the domestic broiler chickens at hatch to investigate the impact of domestication processes on heart rate regulation.

    During the first two postnatal weeks, baseline and stress heart rate progressively increased. After two weeks baseline heart rate decreased while heart rate during acute stress remained high. Adrenergic tone in Red Junglefowl increased as well early suggesting that the increase in heart rate was driven predominantly by adrenergic contributions. The adrenergic tone decreased by age after postnatal week one explaining the concomitant reduction in basal heart rate during this period. Broiler chickens possessed a strong cholinergic tone at hatch indicating that parasympathetic control has been favored perhaps due to heavy selection for somatic growth.

    Nationell ämneskategori
    Biologiska vetenskaper
    Identifikatorer
    urn:nbn:se:liu:diva-117421 (URN)
    Tillgänglig från: 2015-04-27 Skapad: 2015-04-27 Senast uppdaterad: 2015-04-27Bibliografiskt granskad
    3. Domestication Affected Heart Rate Regulation in Juvenile Chickens
    Öppna denna publikation i ny flik eller fönster >>Domestication Affected Heart Rate Regulation in Juvenile Chickens
    2015 (Engelska)Manuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    The domestication process in chickens has involved strong selection for productive traits. There is a broad understanding of phenotypic differences between domestic breeds and their ancestor, the Red Junglefowl (RJF), on fear related behaviors, genetic architecture, physiology and productive traits. Some of these characters can potentially be explained by changes in the activity of the autonomic nervous system. To address these questions we measured heart rate as a proxy for autonomic activity in the Red Junglefowl and compared it with two domestic strains, a broiler (BRO) (meat production) and a White Leghorn strain (HY) (egg production) at two and six weeks of age. Autonomic tones were pharmacologically manipulated in broilers to assess heart rate regulation during maturation. To investigate the dynamics of  autonomic control animals were measured during baseline conditions and during acute stress.

    At two weeks of age baseline heart rate was high in all strains (RJF: 541.2±18.3, HY: 506.8±38.8, BRO: 456.0±22.3) and progressively decreased with age (RJF: 491.3±10.9, HY: 386.8±25.1, BRO:_296.8±26.9). BRO had a lower heart rate compared to RJF and HY, and the differences could not be explained by allometry alone. There was a domestication effect in BRO but not HY, which were in general more similar to RJF. These findings suggest that positive selection for somatic growth has changed heart rate regulation in broilers. During acute stress heart rate did not decrease with age in the same way than baseline values, which means that there is an increased scope for raising heart rate above baseline with age. At least in broilers the increased heart rate scope is due to a recruitment in adrenergic control in absence of a patent cholinergic tone.

    Nationell ämneskategori
    Biologiska vetenskaper
    Identifikatorer
    urn:nbn:se:liu:diva-117422 (URN)
    Tillgänglig från: 2015-04-27 Skapad: 2015-04-27 Senast uppdaterad: 2015-04-27Bibliografiskt granskad
    4. The Strong Selective Sweep Candidate Gene ADRA2C Does Not Explain Domestication Related Changes In The Stress Response Of Chickens
    Öppna denna publikation i ny flik eller fönster >>The Strong Selective Sweep Candidate Gene ADRA2C Does Not Explain Domestication Related Changes In The Stress Response Of Chickens
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    2014 (Engelska)Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 9, nr 8, s. e103218-Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Analysis of selective sweeps to pinpoint causative genomic regions involved in chicken domestication has revealed a strongselective sweep on chromosome 4 in layer chickens. The autoregulatory a-adrenergic receptor 2C (ADRA2C) gene is theclosest to the selective sweep and was proposed as an important gene in the domestication of layer chickens. The ADRA2Cpromoter region was also hypermethylated in comparison to the non-selected ancestor of all domesticated chicken breeds,the Red Junglefowl, further supporting its relevance. In mice the receptor is involved in the fight-or-flight response as itmodulates epinephrine release from the adrenals. To investigate the involvement of ADRA2C in chicken domestication, wemeasured gene expression in the adrenals and radiolabeled receptor ligand in three brain regions comparing the domesticWhite Leghorn strain with the wild ancestor Red Junglefowl. In adrenals ADRA2C was twofold greater expressed than therelated receptor gene ADRA2A, indicating that ADRA2C is the predominant modulator of epinephrine release but no straindifferences were measured. In hypothalamus and amygdala, regions associated with the stress response, and in striatum,receptor binding pIC50 values ranged between 8.1–8.4, and the level was not influenced by the genotyped allele. Becausechicken strains differ in morphology, physiology and behavior, differences attributed to a single gene may be lost in thenoise caused by the heterogeneous genetic background. Therefore an F10 advanced intercross strain between WhiteLeghorn and Red Junglefowl was used to investigate effects of ADRA2C alleles on fear related behaviors and fecundity. Wedid not find compelling genotype effects in open field, tonic immobility, aerial predator, associative learning or fecundity.Therefore we conclude that ADRA2C is probably not involved in the domestication of the stress response in chicken, and thestrong selective sweep is probably caused by selection of some unknown genetic element in the vicinity of the gene.

    Ort, förlag, år, upplaga, sidor
    Public Library of Science, 2014
    Nationell ämneskategori
    Biologiska vetenskaper
    Identifikatorer
    urn:nbn:se:liu:diva-109431 (URN)10.1371/journal.pone.0103218 (DOI)000341105100015 ()25111139 (PubMedID)
    Tillgänglig från: 2014-08-18 Skapad: 2014-08-18 Senast uppdaterad: 2017-12-05
    5. Early stress causes sex-specific, life-long changes in behaviour, levels of gonadal hormones, and gene expression in chickens
    Öppna denna publikation i ny flik eller fönster >>Early stress causes sex-specific, life-long changes in behaviour, levels of gonadal hormones, and gene expression in chickens
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    2015 (Engelska)Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 10, nr 5, artikel-id e0125808Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Early stress can have long-lasting phenotypic effects. Previous research shows that male and female chickens differ in many behavioural aspects, and respond differently to chronic stress. The present experiment aimed to broadly characterize long-term sex differences in responses to brief events of stress experienced during the first weeks of life. Chicks from a commercial egg-laying hybrid were exposed to stress by inducing periods of social isolation during their first three weeks of life, followed by a broad behavioural, physiological and genomic characterization throughout life. Early stressed males, but not females, where more anxious in an open field-test, stayed shorter in tonic immobility and tended to have delayed sexual maturity, as shown by a tendency for lower levels of testosterone compared to controls. While early stressed females did not differ from non-stressed in fear and sexual maturation, they were more socially dominant than controls. The differential gene expression profile in hypothalamus was significantly correlated from 28 to 213 days of age in males, but not in females. In conclusion, early stress had a more pronounced long-term effect on male than on female chickens, as evidenced by behavioral, endocrine and genomic responses. This may either be attributed to inherent sex differences due to evolutionary causes, or possibly to different stress related selection pressures on the two sexes during commercial chicken breeding.

    Ort, förlag, år, upplaga, sidor
    Public Library of Science, 2015
    Nationell ämneskategori
    Biologiska vetenskaper
    Identifikatorer
    urn:nbn:se:liu:diva-117423 (URN)10.1371/journal.pone.0125808 (DOI)000354916100036 ()
    Tillgänglig från: 2015-04-27 Skapad: 2015-04-27 Senast uppdaterad: 2019-03-05Bibliografiskt granskad
    6. 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
  • 14.
    Eliasson, Moa
    et al.
    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, Biologi. Linköpings universitet, Tekniska högskolan.
    Spider monkeys (Ateles geoffroyi) are less sensitive to the odor of aliphatic ketones than to the odor of other classes of aliphatic compounds.2015Ingår i: Neuroscience research, ISSN 0168-0102, E-ISSN 1872-8111, Vol. 99, s. 46-54Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Aliphatic ketones are widely present in body-borne and food odors of primates. Therefore, we used an operant conditioning paradigm and determined olfactory detection thresholds in four spider monkeys for a homologous series of aliphatic 2-ketones (2-butanone to 2-nonanone) and two of their isomers (3- and 4-heptanone). We found that, with the exception of the two shortest-chained ketones, all animals detected concentrations <1ppm (parts per million), and with five odorants individual animals even reached threshold values <0.1ppm. Further, we found a significant correlation between olfactory sensitivity of the spider monkeys and carbon chain length of the 2-ketones which can best be described as a U-shaped function. In contrast, no significant correlation was found between olfactory sensitivity and position of the functional carbonyl group. Across-odorant and across-species comparisons revealed the following: spider monkeys are significantly less sensitive to the odors of aliphatic ketones than to the odor of other classes of aliphatic compounds (1-alcohols, n-aldehydes, n-acetic esters, and n-carboxylic acids) sharing the same carbon length. Spider monkeys do not differ significantly in their olfactory sensitivity for aliphatic ketones from squirrel monkeys and pigtail macaques, but are significantly less sensitive to these odorants compared to human subjects and mice. These findings support the notion that neuroanatomical and genetic properties do not allow for reliable predictions with regard to a species' olfactory sensitivity. Further, we conclude that the frequency of occurrence of a class of odorants in a species' chemical environment does not allow for reliable predictions of the species' olfactory sensitivity.

  • 15.
    Ericsson, Maria
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Domestication and ontogeny effects on the stress response inyoung chickens (Gallus gallus)2016Ingår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 6, artikel-id 6_35818Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Domestication is thought to increase stress tolerance. The connection between stressor exposure,glucocorticoids and behavioural responses has been studied in adults, where domestication effectsare evident. Early stress exposure may induce detrimental effects both in short-and long term.Previous research has reported a lack of glucocorticoid response in newly hatched chickens (Gallusgallus), whereas others have found opposite results. Hence it remains unclear whether the HPA-axis isfunctional from hatch, and if domestication has affected the early post-hatch ontogeny of the stressresponse. Our aims were to investigate the early ontogeny of the HPA-axis and characterize behaviouraland hormonal stress responses in ancestral Red Junglefowl and in two domestic layer strains. Plasmacorticosteone and behavioural responses before and after physical restraint was measured on dayone, nine, 16 and 23 post hatch. The results showed significant increases of corticosterone after stressin all three breeds at all the different ages. The HPA-response decreased with age and was lower inRed Junglefowl. Behavioural responses also decreased with age, and tended to be stronger in RedJunglefowl. In summary, the HPA-axis is reactive from day one, and domestication may have affectedits development and reactivity, alongside with related behaviour responses.

  • 16.
    Evans, Stephen
    et al.
    North-West University, South Africa; University of Venda, South Africa.
    Cole, Nick
    Durrel Wildlife Conservation Trust, Jersey, Channel Islands;Mauritian Wildlife Foundation, Mauritius.
    Kylin, Henrik
    Linköpings universitet, Institutionen för tema, Tema Miljöförändring. Linköpings universitet, Filosofiska fakulteten. North-West University, South Africa.
    Choong Kwet Yive, Nee Sun
    University of Mauritius, Mauritius.
    Tatayah, Vikash
    Mauritian Wildlife Foundation, Mauritius.
    Merven, Jacques
    Raphaël Fishin Corp., Mauritius.
    Bouwman, Hindrik
    North-West University, South Africa.
    Protection of marine birds and turtles at St Brandon’s Rock, Indian Ocean,requires conservation of the entire atoll2016Ingår i: African Journal of Marine Science, ISSN 1814-232X, Vol. 38, nr 3, s. 317-327Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A survey of seabirds and turtles at St Brandon’s Rock, 400 km north of Mauritius, was undertaken in 2010. We estimated that 1.1 million seabirds comprising seven breeding species and excluding non-breeders were present at the archipelago and we counted 279 turtle tracks and nesting pits of green turtles Chelonia mydas. Hawksbill turtles Eretmochelys imbricata were also present. Analyses of 30 different islets that make up the atoll showed that the seabird species mostly partitioned their use of islets based on islet size, with four species preferring larger islets and two species preferring smaller islets. Alien species introduced historically are still present and other threats, such as shipwrecks, remain. We propose conservation and other measures that should adequately protect the birds, turtles and coral reef by treating the atoll as a system.

  • 17.
    Fallahshahroudi, Amir
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Domestication Effects on the Stress Response in Chickens: Genetics, Physiology, and Behaviour2017Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Animal domestication, the process where animals become adapted to living in proximity to humans, is associated with the alteration of multiple traits, including decreased fearfulness and stress response. With an estimated population of 50 billion, the domesticated chicken is the most populous avian species in the world. Hundreds of chicken breeds have been developed for meat and egg production, hobby or research purposes. Multidirectional selection and the relaxation of natural selection in captivity have created immense phenotypic diversity amongst domesticates in a relatively short evolutionary time. The extensive phenotypic diversity, existence of the wild ancestor, and feasibility of intercrossing various breeds makes the chicken a suitable model animal for deciphering genetic determinants of complex traits such as stress response. We used chicken domestication as a model to gain insights about the mechanisms that regulate stress response in an avian species. We studied behavioural and physiological stress response in the ancestral Red Junglefowl and one of its domesticated progenies, White Leghorn. An advanced intercross between the aforementioned breeds was later used to map genetic loci underlying modification of stress response. The general pattern of the stress response in chickens was comparable with that reported in mammals, however we identified distinctive differences in the stress modulatory pathways in chickens. We showed that changes in the expression levels of several stress modulatory genes in the brain, the pituitary and the adrenal glands underlie the observed modified stress response in domesticated chickens. Using quantitative trait loci (QTL) mapping, several QTL underlying stress induced corticosterone, aldosterone and baseline dehydroepiandrosterone (DHEA) levels were detected. As a next step, we combined QTL mapping with gene expression (eQTL) mapping and narrowed two QTL down to the putative causal genes, SERPINA10 and PDE1C. Both of these genes were differentially expressed in the adrenal glands of White Leghorn and the Red Junglefowl, had overlapping eQTL with hormonal QTL, and their expression levels in the adrenal glands were correlated with plasma levels of corticosterone and al-dosterone. These two genes thus serve as strong candidates for further functional investigation concerning modification of the stress response during domestication. This dissertation increase the knowledge about genetics and physiology of the stress response in an avian species and its modification during domestication. Our findings expand the basic knowledge about the stress response in chicken, which can potentially be used to improve welfare through appropriate genetic selection.

    Delarbeten
    1. Domestication effects on behavioural and hormonal responses to acute stress in chickens
    Öppna denna publikation i ny flik eller fönster >>Domestication effects on behavioural and hormonal responses to acute stress in chickens
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    2014 (Engelska)Ingår i: Physiology and Behavior, ISSN 0031-9384, E-ISSN 1873-507X, Vol. 133, s. 161-169Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Comparative studies have shown that alterations in physiology, morphology and behaviour have arisen due tothe domestication. A driving factor behind many of the changes could be a shift in stress responses,withmodifiedendocrine and behavioural profiles. In the present study we compared two breeds of chicken (Gallus gallus), thedomesticWhite Leghorn (WL) egg laying breed and its ancestor, the Red Junglefowl (RJF). Birds were exposed toan acute stress event, invoked by 3 or 10 min of physical restraint. Theywere then continuouslymonitored for theeffects on a wide range of behaviours during a 60 min recovery phase. Blood samples were collected from thechicken at baseline, and after 10 and 60 min following a similar restraint stress, and the samples wereanalyzed for nine endogenous steroids of the HPA and HPG axes. Concentration of the steroids was determinedusing validated liquid chromatography tandem mass spectrometry methods. In RJF, an immediate behaviouralresponse was observed after release from restraint in several behaviours, with a relatively fast return to baselinewithin 1 h. In WL, somebehaviourswere affected for a longer period of time, and others not at all. Concentrationsof corticosterone increasedmore in RJF, but returned faster to baseline compared toWL. A range of baseline levelsfor HPG-related steroids differed between the breeds, and they were generally more affected by the stress in WLthan in RJF. In conclusion, RJF reacted stronger both behaviourally and physiologically to the restraint stress, butalso recovered faster. This would appear to be adaptive under natural conditions, whereas the stress recovery ofdomesticated birds has been altered by domestication and breeding for increased reproductive output.

    Ort, förlag, år, upplaga, sidor
    Elsevier, 2014
    Nyckelord
    Corticosterone Recovery Restraint White Leghorn Red Junglefowl
    Nationell ämneskategori
    Biologiska vetenskaper
    Identifikatorer
    urn:nbn:se:liu:diva-107167 (URN)10.1016/j.physbeh.2014.05.024 (DOI)000340315100022 ()
    Anmärkning

    Funders: Swedish Research Council (VR) [621-2011-4731]; Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning (FORMAS) [221-2011-1088]; ERC (project Genewell) [322206]; Swedish Centre of Excellence in Animal Welfare; ARUP Institute for Clinical and Experimental Pathology

    Tillgänglig från: 2014-06-09 Skapad: 2014-06-09 Senast uppdaterad: 2017-12-05
    2. Domestication Effects on Stress Induced Steroid Secretion and Adrenal Gene Expression in Chickens
    Öppna denna publikation i ny flik eller fönster >>Domestication Effects on Stress Induced Steroid Secretion and Adrenal Gene Expression in Chickens
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    2015 (Engelska)Ingår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 5, s. 1-10, artikel-id 15345Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Understanding the genetic basis of phenotypic diversity is a challenge in contemporary biology. Domestication provides a model for unravelling aspects of the genetic basis of stress sensitivity. The ancestral Red Junglefowl (RJF) exhibits greater fear-related behaviour and a more pronounced HPA-axis reactivity than its domesticated counterpart, the White Leghorn (WL). By comparing hormones (plasmatic) and adrenal global gene transcription profiles between WL and RJF in response to an acute stress event, we investigated the molecular basis for the altered physiological stress responsiveness in domesticated chickens. Basal levels of pregnenolone and dehydroepiandrosterone as well as corticosterone response were lower in WL. Microarray analysis of gene expression in adrenal glands showed a significant breed effect in a large number of transcripts with over-representation of genes in the channel activity pathway. The expression of the best-known steroidogenesis genes were similar across the breeds used. Transcription levels of acute stress response genes such as StAR, CH25 and POMC were upregulated in response to acute stress. Dampened HPA reactivity in domesticated chickens was associated with changes in the expression of several genes that presents potentially minor regulatory effects rather than by means of change in expression of critical steroidogenic genes in the adrenal.

    Ort, förlag, år, upplaga, sidor
    Nature Publishing Group, 2015
    Nationell ämneskategori
    Bioinformatik och systembiologi
    Identifikatorer
    urn:nbn:se:liu:diva-122305 (URN)10.1038/srep15345 (DOI)000362885300001 ()26471470 (PubMedID)
    Anmärkning

    Funding agencies: Swedish Research Council (VR) [621-2011-4731]; Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning (FORMAS) [221-2011-1088]; SRC [621-2011-5523]; ERC [322206]; Swedish Centre of Excellence in Animal Welfare

    Tillgänglig från: 2015-10-28 Skapad: 2015-10-28 Senast uppdaterad: 2017-12-01
    3. Genetic and Targeted eQTL Mapping Reveals Strong Candidate Genes Modulating the Stress Response During Chicken Domestication.
    Öppna denna publikation i ny flik eller fönster >>Genetic and Targeted eQTL Mapping Reveals Strong Candidate Genes Modulating the Stress Response During Chicken Domestication.
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    2017 (Engelska)Ingår i: G3: Genes, Genomes, Genetics, ISSN 2160-1836, E-ISSN 2160-1836, Vol. 7, nr 2Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    The stress response has been largely modified in all domesticated animals, offering a strong tool for genetic mapping. In chickens, ancestral Red Junglefowl react stronger both in terms of physiology and behavior to a brief restraint stress than domesticated White Leghorn, demonstrating modified functions of the hypothalamic-pituitary-adrenal (HPA) axis. We mapped quantitative trait loci (QTL) underlying variations in stress-induced hormone levels using 232 birds from the 12th generation of an advanced intercross between White Leghorn and Red Junglefowl, genotyped for 739 genetic markers. Plasma levels of corticosterone, dehydroepiandrosterone (DHEA), and pregnenolone (PREG) were measured using LC-MS/MS in all genotyped birds. Transcription levels of the candidate genes were measured in the adrenal glands or hypothalamus of 88 out of the 232 birds used for hormone assessment. Genes were targeted for expression analysis when they were located in a hormone QTL region and were differentially expressed in the pure breed birds. One genome-wide significant QTL on chromosome 5 and two suggestive QTL together explained 20% of the variance in corticosterone response. Two significant QTL for aldosterone on chromosome 2 and 5 (explaining 19% of the variance), and one QTL for DHEA on chromosome 4 (explaining 5% of the variance), were detected. Orthologous DNA regions to the significant corticosterone QTL have been previously associated with the physiological stress response in other species but, to our knowledge, the underlying gene(s) have not been identified. SERPINA10 had an expression QTL (eQTL) colocalized with the corticosterone QTL on chromosome 5 and PDE1C had an eQTL colocalized with the aldosterone QTL on chromosome 2. Furthermore, in both cases, the expression levels of the genes were correlated with the plasma levels of the hormones. Hence, both these genes are strong putative candidates for the domestication-induced modifications of the stress response in chickens. Improved understanding of the genes associated with HPA-axis reactivity can provide insights into the pathways and mechanisms causing stress-related pathologies.

    Ort, förlag, år, upplaga, sidor
    The Genetics Society, 2017
    Nyckelord
    animal, domestication, quantitative trait, genes, corticosterone, aldosterone
    Nationell ämneskategori
    Biologiska vetenskaper
    Identifikatorer
    urn:nbn:se:liu:diva-134649 (URN)10.1534/g3.116.037721 (DOI)000394357100015 ()27974436 (PubMedID)
    Anmärkning

    Funding agencies: Swedish Research Council (SRC) (Vetenskapsradet) [621-2011-4731]; Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning (Forskningsradet for Miljo, Areella Naringar och Samhallsbyggande) [221-2011-1088]; European Research Co

    Tillgänglig från: 2017-02-21 Skapad: 2017-02-21 Senast uppdaterad: 2017-11-29
    4. QTL mapping of stress related gene expression in a cross between domesticated chickens and ancestral red junglefowl.
    Öppna denna publikation i ny flik eller fönster >>QTL mapping of stress related gene expression in a cross between domesticated chickens and ancestral red junglefowl.
    Visa övriga...
    2017 (Engelska)Ingår i: Molecular and Cellular Endocrinology, ISSN 0303-7207, E-ISSN 1872-8057, Vol. 446, s. 52-58, artikel-id S0303-7207(17)30090-4Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Domestication of animals is associated with numerous alterations in physiology, morphology, and behavior. Lower reactivity of the hypothalamic-pituitary-adrenal (HPA) axis and reduced fearfulness is seen in most studied domesticates, including chickens. Previously we have shown that the physiological stress response as well as expression levels of hundreds of genes in the hypothalamus and adrenal glands are different between domesticated White Leghorn and the progenitor of modern chickens, the Red Junglefowl. To map genetic loci associated with the transcription levels of genes involved in the physiological stress response, we conducted an eQTL analysis in the F12 generation of an inter-cross between White Leghorn and Red Junglefowl. We selected genes for further studies based on their known function in the regulation of the HPA axis or sympathoadrenal (SA) system, and measured their expression levels in the hypothalamus and the adrenal glands after a brief stress exposure (physical restraint). The expression values were treated as quantitative traits for the eQTL mapping. The plasma levels of corticosterone were also assessed. We analyzed the correlation between gene expression and corticosterone levels and mapped eQTL and their potential effects on corticosterone levels. The effects on gene transcription of a previously found QTL for corticosterone response were also investigated. The expression levels of the glucocorticoid receptor (GR) in the hypothalamus and several genes in the adrenal glands were correlated with the post-stress levels of corticosterone in plasma. We found several cis- and trans-acting eQTL for stress-related genes in both hypothalamus and adrenal. In the hypothalamus, one eQTL for c-FOS and one QTL for expression of GR were found. In the adrenal tissue, we identified eQTL for the genes NR0B1, RGS4, DBH, MAOA, GRIN1, GABRB2, GABRB3, and HSF1. None of the found eQTL were significant predictors of corticosterone levels. The previously found QTL for corticosterone was associated with GR expression in hypothalamus. Our data suggests that domestication related modification in the stress response is driven by changes in the transcription levels of several modulators of the HPA and SA systems in hypothalamus and adrenal glands and not by changes in the expression of the steroidogenic genes. The presence of eQTL for GR in hypothalamus combined with the negative correlation between GR expression and corticosterone response suggests GR as a candidate for further functional studies regarding modification of stress response during chicken domestication.

    Nyckelord
    Animal domestication, HPA axis, QTL, Stress response, eQTL
    Nationell ämneskategori
    Biologiska vetenskaper
    Identifikatorer
    urn:nbn:se:liu:diva-136027 (URN)10.1016/j.mce.2017.02.010 (DOI)000399509600006 ()28189567 (PubMedID)
    Anmärkning

    Funding agencies: Swedish Research Council (VR) [621-2011-4731]; Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning (FORMAS) [221-2011-1088]; ERC [Genewell 322206]; SRC grant [VR 621-2011-4423, 2015-4870]; Swedish Centre of Excellence in A

    Tillgänglig från: 2017-03-27 Skapad: 2017-03-27 Senast uppdaterad: 2018-09-27
  • 18.
    Franklin, Craig E.
    et al.
    University of Queensland, Brisbane, Australia.
    Farrell, Anthony P.
    University of British Columbia, Vancouver, Canada.
    Altimiras, Jordi
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Axelsson, Michael
    University of Gothenburg, Sweden.
    Thermal dependence of cardiac function in arctic fish: implications of a warming world2013Ingår i: Journal of Experimental Biology, ISSN 0022-0949, E-ISSN 1477-9145, Vol. 216, s. 4251-4255Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    With the Arctic experiencing one of the greatest and most rapid increases in sea temperatures in modern time, predicting how Arctic marine organisms will respond to elevated temperatures has become crucial for conservation biology. Here, we examined the thermal sensitivity of cardiorespiratory performance for three closely related species of sculpins that inhabit the Arctic waters, two of which, Gymnocanthus tricuspis and Myoxocephalus scorpioides, have adapted to a restricted range within the Arctic, whereas the third species, Myoxocephalus scorpius, has a wider distribution. We tested the hypothesis that the fish restricted to Arctic cold waters would show reduced cardiorespiratory scope in response to an increase in temperature, as compared with the more eurythermal M. scorpius. As expected from their biogeography, M. scorpioides and G. tricuspis maximised cardiorespiratory performance at temperatures between 1 and 4 degrees C, whereas M. scorpius maximised performance over a wider range of temperatures (1-10 degrees C). Furthermore, factorial scope for cardiac output collapsed at elevated temperature for the two high-latitude species, negatively impacting their ability to support aerobically driven metabolic processes. Consequently, these results concurred with our hypothesis, suggesting that the sculpin species restricted to the Arctic are likely to be negatively impacted by increases in ocean temperatures.

  • 19.
    Gavrilets, Sergey
    et al.
    Departments of Ecology and Evolutionary Biology and Mathematics, University of Tennessee, Knoxville,USA.
    Arnqvist, Göran
    Department of Ecology and Environmental Science, University of Umeå, Sweden.
    Friberg, Urban
    Department of Ecology and Environmental Science, University of Umeå, Sweden.
    The evolution of female mate choice by sexual conflict2001Ingår i: Proceedings of the Royal Society of London Series B, ISSN 0080-4649, Vol. 268, nr 1466, s. 531-539Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Although empirical evidence has shown that many male traits have evolved via sexual selection by female mate choice, our understanding of the adaptive value of female mating preferences is still very incomplete. It has recently been suggested that female mate choice may result from females evolving resistance rather than attraction to males, but this has been disputed. Here, we develop a quantitative genetic model showing that sexual conflict over mating indeed results in the joint evolution of costly female mate choice and exaggerated male traits under a wide range of circumstances. In contrast to traditional explanations of costly female mate choice, which rely on indirect genetic benefits, our model shows that mate choice can be generated as a side–effect of females evolving to reduce the direct costs of mating.

  • 20.
    Girndt, Antje
    et al.
    Max Planck Institute Ornithol, Germany; Imperial Coll London, England; University of Konstanz, Germany.
    Cockburn, Glenn
    Max Planck Institute Ornithol, Germany; University of Konstanz, Germany.
    Sanchez-Tojar, Alfredo
    Max Planck Institute Ornithol, Germany; Imperial Coll London, England; University of Konstanz, Germany.
    Lovlie, Hanne
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Schroeder, Julia
    Max Planck Institute Ornithol, Germany; Imperial Coll London, England.
    Method matters: Experimental evidence for shorter avian sperm in faecal compared to abdominal massage samples2017Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 12, nr 8, artikel-id e0182853Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Birds are model organisms in sperm biology. Previous work in zebra finches, suggested that sperm sampled from males faeces and ejaculates do not differ in size. Here, we tested this assumption in a captive population of house sparrows, Passer domesticus. We compared sperm length in samples from three collection techniques: female dummy, faecal and abdominal massage samples. We found that sperm were significantly shorter in faecal than abdominal massage samples, which was explained by shorter heads and midpieces, but not flagella. This result might indicate that faecal sampled sperm could be less mature than sperm collected by abdominal massage. The female dummy method resulted in an insufficient number of experimental ejaculates because most males ignored it. In light of these results, we recommend using abdominal massage as a preferred method for avian sperm sampling. Where avian sperm cannot be collected by abdominal massage alone, we advise controlling for sperm sampling protocol statistically.

  • 21.
    Griesser, Michael
    et al.
    University of Zurich, Switzerland; University of Bern, Switzerland; Uppsala University, Sweden.
    Mourocq, Emeline
    University of Zurich, Switzerland; University of Bern, Switzerland.
    Barnaby, Jonathan
    Uppsala University, Sweden.
    Bowgen, Katharine M.
    Bournemouth University, England.
    Eggers, Sonke
    Uppsala University, Sweden; Swedish University of Agriculture Science, Sweden.
    Fletcher, Kevin
    Uppsala University, Sweden.
    Kozma, Radoslav
    Uppsala University, Sweden.
    Kurz, Franziska
    Freiburg, Germany.
    Laurila, Anssi
    Uppsala University, Sweden.
    Nystrand, Magdalena
    Uppsala University, Sweden; Monash University, Australia.
    Sorato, Enrico
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Ekman, Jan
    Uppsala University, Sweden.
    Experience buffers extrinsic mortality in a group-living bird species2017Ingår i: Oikos, ISSN 0030-1299, E-ISSN 1600-0706, Vol. 126, nr 9, s. 1258-1268Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Extrinsic mortality has a strong impact on the evolution of life-histories, prey morphology and behavioural adaptations, but for many animals the causes of mortality are poorly understood. Predation is an important driver of extrinsic mortality and mobile animals form groups in response to increased predation risk. Furthermore, in many species juveniles suffer higher mortality than older individuals, which may reflect a lower phenotypic quality, lower competitiveness, or a lack of antipredator or foraging skills. Here we assessed the causes of mortality for 371 radio tagged Siberian jays. This sedentary bird species lives in family groups that contain a breeding pair as well as related and unrelated non-breeders. Ninety-five percent of death were due to predation (n = 59 out of 62 individuals) and most individuals were killed by Accipiter hawks. Multivariate Cox proportional hazards models showed that non-breeders had a lower survival than breeders, but only in territories in managed forest with little visual cover. Examining breeders, only sex influenced survival with males having a lower survival than females. For non-breeders, juveniles had lower survival than older non-breeders, and those on managed territories had lower survival than those on unmanaged territories. Additionally, a low feather quality reduced the survival probability of non-breeders only. Thus, living on managed territories and having a low feature quality affected only non-breeders, particularly juveniles. These findings add to previous research demonstrating that juvenile Siberian jays acquire critical antipredator skills from experienced group members. Thus, experience can buffer extrinsic mortality, highlighting that group living not only provides safety in numbers, but also provide social opportunities to learn critical life-skills.

  • 22.
    Grozelier, Anna
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Labrador and German shepherd breed differences in dog-human communication2015Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    As our long-term companions, dogs’ communication with us is perhaps the most developed of all human- animal ones. This study was aimed to investigate breed differences of German Shepherds and Labradors in dog-human communication. This was obtained through two tests: a problem-solving task and a pointing test. These two tests target both directions of communication: how much dogs understand and respond to the pointing and how they communicate with humans when facing a problem. Additionally, hair cortisol was measured in the dogs and dog owners filled a behavioural questionnaire (C-BARQ). The main breed difference I found was that Labradors performed better in both tests. I also found that the latency of the dogs’ choices in the pointing test correlated with many factors, e.g. they chose quicker when: choosing correctly, when they had many physical contacts with the experimenter in the problem-solving task, when they were more intense, energetic dogs, when they had higher hair cortisol levels and when they had a confident body posture. This indicates that the latency of choice could depend on the confidence of the dog and on the trust in the experimenter as well as on energy level and focus ability. Overall, this study revealed a limited amount of breed differences, compared to a parallel study on Labrador types (hunting and show dogs), showing that intra-breed differences can be more important than inter-breed ones on a behavioural level. 

  • 23.
    Henriksen, Rie
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Johnsson, Martin
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Andersson, L
    Department of Medical Biochemistry and Microbiology, Uppsala University, Sweden.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Wright, Dominic
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    The domesticated brain: genetics of brain mass and brain structure in an avian species.2016Ingår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 6Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    As brain size usually increases with body size it has been assumed that the two are tightly constrained and evolutionary studies have therefore often been based on relative brain size (i.e. brain size proportional to body size) rather than absolute brain size. The process of domestication offers an excellent opportunity to disentangle the linkage between body and brain mass due to the extreme selection for increased body mass that has occurred. By breeding an intercross between domestic chicken and their wild progenitor, we address this relationship by simultaneously mapping the genes that control inter-population variation in brain mass and body mass. Loci controlling variation in brain mass and body mass have separate genetic architectures and are therefore not directly constrained. Genetic mapping of brain regions indicates that domestication has led to a larger body mass and to a lesser extent a larger absolute brain mass in chickens, mainly due to enlargement of the cerebellum. Domestication has traditionally been linked to brain mass regression, based on measurements of relative brain mass, which confounds the large body mass augmentation due to domestication. Our results refute this concept in the chicken.

  • 24.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Hundens språk och tankar2011 (uppl. 1)Bok (Övrigt vetenskapligt)
    Abstract [sv]

    Det är svårt att tänka sig ett mänskligt liv utan hundar! Sedan vi levde som jägare och samlare har hunden följt oss människor. Per Jensen, professor i etologi, har skrivit en bok om hundens beteende, språk och tankeförmåga och beskriver pedagogiskt hur kunskapsläget är idag. Ny fakta blir här tillgänglig för en intresserad allmänhet. Boken ger en unik inblick i vad den moderna vetenskapen har att säga om hundens inre liv.

  • 25.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Mechanisms and function in dog behaviour2007Ingår i: The behavioural biology of dogs / [ed] Per Jensen, Wallingford, Oxfordshire, UK: CABI Publishing, 2007, s. 61-75Kapitel i bok, del av antologi (Övrigt vetenskapligt)
    Abstract [sv]

    The long-established connection between dogs and humans has given rise to behavioural adaptations typical of mutualism, which ties our own evolutionary and historical paths closely to those of the dog. Written by experts in different areas, this book presents an up-to-date account of the behavioural biology of dogs. Split in 3 parts, the book addresses the specific aspects of behavioural biology. The first part deals with the evolution and development of the dog, whereas the next part deals with basic aspects of dog behaviour. The final part emphasises on the behavioural problems, their prevention and cure.

  • 26.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    The behavioural biology of dogs2007Samlingsverk (redaktörskap) (Övrigt vetenskapligt)
    Abstract [sv]

    The long-established connection between dogs and humans has given rise to behavioural adaptations typical of mutualism, which ties our own evolutionary and historical paths closely to those of the dog. Written by experts in different areas, this book presents an up-to-date account of the behavioural biology of dogs. Split in 3 parts, the book addresses the specific aspects of behavioural biology. The first part deals with the evolution and development of the dog, whereas the next part deals with basic aspects of dog behaviour. The final part emphasises on the behavioural problems, their prevention and cure.

  • 27.
    Karczmarz, Veronika
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska högskolan.
    Thermal comfort in young broiler chickens (Gallus gallus domesticus) inferred from metabolic expenses.2014Självständigt arbete på grundnivå (kandidatexamen), 10,5 poäng / 16 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The thermoneutral zone (TNZ) curve lies between the ambient temperatures (Ta) where an endothermic animal uses the least amount of energy to maintain a balance between the heat production from the animal’s own metabolism and the heat lost to the environment. If the animal is exposed to Ta’s over the upper critical temperature (UCT), which is the highest temperature that is still in the TNZ, the animals have to use energy to cool down. If they are exposed to temperatures lower than the lower critical temperature (LCT), which is the lowest temperature that is still in the TNZ, the animal have to use energy to warm up. In the present study oxygen consumption was measured at different Ta’s to determine the TNZ in two and three week old broiler chickens (Gallus gallus domesticus). Two different protocols were used and compared, a pseudorandom protocol in which chickens were exposed to seven temperatures in two hour periods for each run and a more typical progressive protocol in which Ta decreased gradually, one or two degrees per hour. The TNZ in two weeks old chickens was between 30.7 ˚C- 36.4 ˚C and between 28.8 ˚C- 32.7 ˚C in the three weeks old chickens. In chickens the TNZ shifts remarkably during the first few weeks of life towards lower temperatures as the animals acquire thermoregulatory competence. The method with a pseudorandom protocol takes more factors, like activity, into consideration than a typical progressive protocol.

  • 28.
    Karlsson, Anna-Carin
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Fallahsharoudi, Amir
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Johnsen, Hanna
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Hagenblad, Jenny
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Wright, Dominic
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Andersson, Leif
    Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    A domestication related mutation in the thyroid stimulating hormonereceptor gene (TSHR) modulates photoperiodic response andreproduction in chickens2016Ingår i: General and Comparative Endocrinology, ISSN 0016-6480, E-ISSN 1095-6840, Vol. 228, s. 69-78Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The thyroid stimulating hormone receptor gene (TSHR) has been suggested to be a ‘‘domestication locus”in the chicken. A strong selective sweep over TSHR in domestic breeds together with significant effects ofa mutation in the gene on several domestication related traits, indicate that the gene has been importantfor chicken domestication. TSHR plays a key role in the signal transduction of seasonal reproduction,which is characteristically less strict in domestic animals. We used birds from an advanced intercross linebetween ancestral Red Junglefowl (RJF) and domesticated White Leghorn (WL) to investigate effects ofthe mutation on reproductive traits as well as on TSHB, TSHR, DIO2 and DIO3 gene expression duringaltered day length (photoperiod). We bred chickens homozygous for either the mutation (d/d) or wildtype allele (w/w), allowing assessment of the effect of genotype at this locus while also controlling forbackground variation in the rest of the genome. TSHR gene expression in brain was significantly lowerin both d/d females and males and d/d females showed a faster onset of egg laying at sexual maturity thanw/w. Furthermore, d/d males showed a reduced testicular size response to decreased day length, andlower levels of TSHB and DIO3 expression. Additionally, purebred White Leghorn females kept under naturalshort day length in Sweden during December had active ovaries and lower levels of TSHR and DIO3expression compared to Red Junglefowl females kept under similar conditions. Our study indicates thatthe TSHR mutation affects photoperiodic response in chicken by reducing dependence of seasonal reproduction,a typical domestication feature, and may therefore have been important for chickendomestication.

  • 29.
    Kim, Sunghee
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Olfactory discrimination ability of South African fur seals (Arctocephalus pusillus) for enantiomers2012Självständigt arbete på avancerad nivå (masterexamen), 80 poäng / 120 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The sense of smell in marine mammals is traditionally thought to be poor. However, increasing evidence suggests that pinnipeds may use their sense of smell in a variety of behavioral contexts including communication, foraging, food selection, and reproduction. Using a food-rewarded two-choice instrumental conditioning paradigm, I assessed the ability of South African fur seals, Arctocephalus pusillus, to discriminate between 12 enantiomeric odor pairs, that is, between odorants that are identical in structure except for chirality. The fur seals significantly discriminated between eight out of the twelve odor pairs (according to p < 0.05, with carvone, dihydrocarvone, dihydrocarveol, limonene oxide, menthol, beta-citronellol, fenchone, and alpha-pinene), and failed with only four odor pairs (isopulegol, rose oxide, limonene, and camphor). No significant differences in performance were found between the animals (p > 0.05). Cross-species comparisons between the olfactory performance of the fur seals and that of other species previously tested on the same set of odor pairs lend further support to the notion that the relative size of the olfactory bulbs is not a reliable predictor of olfactory discrimination abilities. The results of the present study suggest that sense of smell may play an important and hitherto underestimated role in regulating the behavior of fur seals.

  • 30.
    Kylin, Henrik
    Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    At-sea observation of the spring migration and pair bonding of ivory gulls (Pagophila eburnea) around Svalbard and East Greenland.2011Ingår i: Polar Research, ISSN 0800-0395, E-ISSN 1751-8369, Vol. 30, nr 6421, s. 1-7Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Because of logistical constraints little previous information exists on ivory gulls (Pagophila eburnea) in the waters around Svalbard and the east coast of Greenland in late winter/early spring. The Swedish Arctic Ocean 2002 expedition investigated these areas at that time of year and in this paper I report on the observations of ivory gulls made during the expedition. The ivory gull was essentially absent from open waters but was the most common seabird in areas with pack ice, showing behavioural differences depending on local conditions. Generally, the number of ivory gulls was low when there was little plankton in the water. Ivory gulls followed the ship depending on the availability of food items in the wake and also depending on competition from other species, particularly glaucous gulls (Larus hyperboreus). Although ivory gulls were present in most of Fram Strait and the northern part of the East Greenland Current during 6 and 19 May, sightings were few and correlated to the amount of plankton in the water. Aggregations of several hundred were seen on the ice where copulation and other social interaction took place. A previously undescribed pair bonding behaviour during which females seemed to select between two competing males was observed north of Svalbard on 30 April - 1 May. Off Scoresby Sound on 25 May, more than 700 birds were seen migrating north, while farther south along the Greenland coast on 30 May there was little indication of migration although many ivory gulls were seen.

  • 31.
    Kylin, Henrik
    Linköpings universitet, Institutionen för tema, Tema vatten i natur och samhälle. Linköpings universitet, Filosofiska fakulteten.
    Birds and mammals off the northern coast of Argentina: first report of an association between birds and a feeding Pygmy Right Whale Caperea marginata2013Ingår i: Ornis Svecica, ISSN 1102-6812, Vol. 23, nr 3-4, s. 117-122Artikel i tidskrift (Refereegranskat)
    Abstract [sv]

    Rio dela Plata är ett stort deltaområde i vilket flera stora floder mynnar. Avrinningsområdet är Sydamerikas näst största. Utanför Rio de la Platas mynning möter det näringsrika sötvattnet den kalla Malvinas- (Falklands-) strömmen från söder och den varma Brasilienströmmen från norr. Havet utanför norra Argentinaoch Uruguay är därför en potentiell mötesplats för marina fåglar och däggdjur från såväl subtropiska som tempererade och subantarktiska vatten som dras till området p.g.a. den höga planktonproduktionen. Under eftermiddagen 20 november 2007 var isbrytaren Oden på väg till Antarktis genom sötvattensplymen söderut. Observationsförhållandena var exceptionellt goda, med stiltje och spegelblankt hav. Totalt sågs 42 fågelarter, elva arter valar, delfiner och tumlare, och tre sälarter. Den mest unika observationen var en födosökande dvärgrätval. Dvärgrätval äter i huvudsak hoppkräftor, och fågelarter som äter samma typ av föda, brednäbbad simsnäppa, smalnäbbade valfågel, och havslöpare, plockade upp smådjur som sipprade ut mellan valens barder då den kom upp till ytan efter dyk.

  • 32.
    Kylin, Henrik
    Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Birds off Scoresby Sound, Eastern Greenland, in the spring of 2002: Fåglar utanför Scoresbysund, Östgrönland, våren 20022006Ingår i: Ornis Svecica, ISSN 1102-6812, Vol. 16, s. 164-167Artikel i tidskrift (Refereegranskat)
    Abstract [sv]

    Under den svenska expeditionen “Arctic Ocean 2002” tillbringades några dagar drivande i isen utanför Scoresbysund, Östgrönland, i skydd undan en storm på Nordatlanten. När stormen avtog 25 maj kom flyttningsrörelser igång bland flera olika fågelarter. Mest intressant är mer än 700 ismåsar som flyttade mot norr. Flera samlades också runt fartyget där olika parbildningsbeteenden och parning iaktogs. Ett par flockar kustpipare flög mot nordost; en mycket märklig observation eftersom kustpipare normalt inte skall finnas på Grönland. Kärrsnäpor sågs flytta både i östlig och västlig riktning, d.v.s. både in mot och bort ifrån Grönland, medan sandlöpare och skärsnäppor endast flyttade mot väster mot Grönland. Under kvällen iaktogs ett omfattande sträck norrut längs med kusten av småvadare, förmodligen mest kustsnäppor. Flyttning iaktogs också bland ejder, fjällabb och lappsparv, medan vittrut, tretåig mås, spetsbergsgrissla, tobisgrissla och alkekung sågs under födosök.

  • 33.
    Kylin, Henrik
    Linköpings universitet, Institutionen för tema, Tema vatten i natur och samhälle. Linköpings universitet, Filosofiska fakulteten.
    Finns det slemsvampar i havet?2013Ingår i: Fauna och flora : populär tidskrift för biologi, ISSN 0014-8903, Vol. 108, nr 1, s. 9-9Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 34.
    Kylin, Henrik
    Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Juvenile Black-legged Kittiwakes Rissa tridactyla with deformed bills and clubfeet in the Barents Sea2005Ingår i: Ornis Svecica, ISSN 1102-6812, Vol. 15, s. 149-152Artikel i tidskrift (Refereegranskat)
    Abstract [sv]

    Då expeditionen ”Arctic Ocean-96” passerade Barents hav 21–24 juli 1996 iakttogs minst 10 juvenila tretåiga måsar med missbildade näbbar och/eller fötter. Ytterligare minst två exemplar sågs väst om Svalbard 20–21 september. Missbildningarna var förlängd eller förvriden övre eller nedre näbbhalva, helt korslagd näbb och/eller klumpfot. Antalet missbildade individ är högre än vad som kan förklaras med naturlig frekvens av missbildningar. Missbildningar av liknande typ hos olika sjöfåglar i de Stora Sjöarna i Nordamerika har kopplats till höga halter klororganiska miljöföroreningar av typen PCB eller ”dioxiner”, men liknande missbildningar kan också framkallas av D-vitaminbrist, sjukdomar, tungmetaller eller radioaktivitet. Även kombinationer av en eller flera av dessa orsaker är tänkbara. Med nuvarande kunskapsläge går det inte att dra säkra slutsatser om orsakerna till att ovanligt många missbildningar observerades i området kring Barents Hav under expeditionen 1996.

  • 35.
    Kylin, Henrik
    Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Kashmir Flycatcher Ficedula subrubra nesting in Sri Lanka?2002Ingår i: Oriental Bird Club. Bulletin, ISSN 0268-9634, Vol. 36, s. 73-Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    Observations indicating that Kashmir Flycatchers may nest in Sri Lanka are reported. This species normally nests in the north-eastern part of the Indian subcontinent, and winter in Sri Lanka.

  • 36.
    Kylin, Henrik
    Linköpings universitet, Institutionen för tema, Tema vatten i natur och samhälle. Linköpings universitet, Filosofiska fakulteten.
    Short-tailed Shearwaters Puffinus tenuirostris forage in Grey Whale Eschrichtius robustus Mud Plumes2013Ingår i: Ornis Svecica, ISSN 1102-6812, Vol. 23, s. 114-116Artikel i tidskrift (Refereegranskat)
    Abstract [sv]

    Gråvalar Eschrichtius robustus är de enda stora valar som är söker föda genom att filtrera bottensediment. Då valen återkommer till ytan uppstår ett sedimentmoln då sediment pressas ut mellan barderna.

     

     Under den svenska expeditionen “Beringia 2005ˮ sågs flockar om flera 10 000 övervintrande kortstjärtade liror Puffinus tenuirostris i Tjuktjerhavet. I områden där även födosökande gråvalar förekom, sökte lirorna aktivt föda i sedimentmolnen. Kortstjärtade liror lever i första hand på krill, och i de områden där de stora flockarna av liror observerades förekom höga koncentrationer plankton. Eftersom lirorna trotts tillgången på plankton dras till sedimentmolnen måste dessa innehålla organismer som är extra attraktiva som föda. Det är sedan tidigare känt att andra havsfåglar dras till sedimentmolnen, men detta är första gången det beskrivs för kortstjärtad lira.

  • 37.
    Kylin, Henrik
    et al.
    Norwegian Institute for Air Research, Polar Environmental Centre, Tromsø, Norway.
    Bouwman, Henk
    School of Environmental Sciences and Development (Zoology), North-West University, Potchefstroom, South Africa.
    Evans, Steven W.
    School of Environmental Sciences and Development (Zoology), North-West University, Potchefstroom, South Africa.
    Evaluating threats to an endangered species by proxy: air pollution as threat to the blue swallow (Hirundo atrocaerulea) in South Africa2011Ingår i: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 18, nr 2, s. 282-290Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background, aim, and scope: The blue swallow (Hirundo atrocaerulea) is one of the most threatened bird species in southern Africa. Among terrestrial birds, its plumage is known to be the most water repellent, an adaptation to foraging on the wing in dense fog. Despite this uniqueadaptation, the nesting success of the blue swallow at the Blue Swallow Natural Heritage Site (BSNHS) is lower during years with high incidence of fog. As the phenomenon is not observed at other nesting sites, we hypothesized that this is due to changes in the air chemistry at the BSNHS. In the immediate proximity of the BSNHS, plantations of exotic trees (e.g., pines and eucalypts), rich in volatile organic compounds (VOCs), are dominant features. In addition, air pollution from the Johannesburg area is transported with the surface winds and mix withVOCs released from exotic trees. Together with the high humidity and high elevation, these conditions may result in the formation of sulphonates. Sulphonates are strong detergents, and the presence of these in the fog could lead to decreased water repellence of the plumage. This study was performed in order to determine the occurrence and distribution of sulphonates in the BSNHS and to compare these with sulphonates formed in other locations in South Africa. Because the blue swallow is endangered, pine needles were used as proxy to detect formation of sulphonates.

    Methods: We sampled pine needles with different exposure to air pollutants, in climates with different humidity, and at different elevation and analyzed these for sulphonates using mass spectrometry.

    Results: Pine needles from high elevations and the BSNHS, with high humidity, and exposure to air pollution contained significantly higher concentrations of sulphonates than pine needles from low elevations or from high elevations with a dryer climate or a different combination of air pollutants.

    Conclusions: These findings lead to two conclusions. First, the occurrence and distribution of sulphonates may be explained by chemical reactions between sulphur dioxide and organic compounds in the humid air induced by ultraviolet radiation. Second, elevated concentrations of sulphonates in the fog could affect the water repellence of the blue swallow plumage, possibly decreasing their capacity to forage in the fog. We cannot prove conclusively that this is the reason why the number of blue swallows atthe BSNHS has decreased dramatically, but for endangered species, we may have to rely on proxies to draw conclusions about outside threats. All such information should be valuable in devising protection plans for species under threat.

    Recommendations and perspectives: The use of proxies to elucidate threats to endangered species should be evaluated in a broad scale. The mist-belt habitat in general is threatened by many human activities. These findings indicate that air pollution and the proximity of volatile organic compound (VOC) sources close to mist-belt habitat refuges may be an unrecognised conservation threat to the animals inhabiting them.

  • 38.
    Kylin, Henrik
    et al.
    Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences.
    Bouwman, Henk
    North-West University, South Africa.
    Louette, Michel
    Royal Museum for Central Africa, Belgium.
    Distribution of the subspecies of the Lesser Black-backed Gull Larus fuscus in sub-Saharan Africa2011Ingår i: Bird Study, ISSN 0006-3657, E-ISSN 1944-6705, Vol. 58, nr 2, s. 186-192Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Capsule The wintering area of the nominate subspecies of Lesser Black-backed Gull Larus fuscus fuscus is from Ethiopia across Uganda and the Congo basin to the Atlantic, while L. f. intermedius and L. f. graellsii winters in westernmost Africa.

    Aims To clarify the wintering distributions of the subspecies of Lesser Black-backed Gull.

    Methods We compiled, mapped, and analyzed available data on ring recoveries (269) and verified museum specimens (22) south of 25°N.

    Results The wintering area of L. f. fuscus as described in standard reference literature (East Africa) is wrong; more rings have been recovered in the Congo basin and along the Atlantic coast than on the eastern seaboard. L. f. intermedius and L. f. graellsii winter mainly in westernmost Africa with some ring recoveries south and east of Senegal. There are no verifiable finds of the latter two subspecies south of the equator. Ring recoveries suggest leap-frog migration.

    Conclusions We have updated the distribution of L. f. fuscus, L. f. intermedius and L. f. graellsii in sub-Saharan Africa and found it to be different from previous authorities. Climate change may have a larger effect on L. f. intermedius and L. f. graellsii than on L. f. fuscus.

  • 39.
    Kylin, Henrik
    et al.
    Linköpings universitet, Institutionen för tema, Tema vatten i natur och samhälle. Linköpings universitet, Filosofiska fakulteten.
    Mitchell, David
    Upper Hartfield, Ease Sussex, England.
    Seraoui, El-Hacène
    Ambilly, France.
    Buyck, Bart
    National Museum of Natural History, Paris, France.
    Myxomycetes from Papua New Guinea and New Caledonia2013Ingår i: Fungal diversity, ISSN 1560-2745, E-ISSN 1878-9129, Vol. 59, nr 1, s. 33-44Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We present a compilation of all myxomycetes recorded in Papua New Guinea (PNG) and New Caledonia (NC). Specimens were collected during field trips in September 1983 – January 1984 to both territories and in August 1991, October 2007, and April 2009 to NC. Bark and dung samples for moist chamber cultures were collected during the field trips in September 1983 – January 1984 (PNG and NC) and in August 1991 and October 2007 (NC). In addition, information from previous publications and unpublished specimens in the herbarium at the Plant Protection Instituted in Port Moresby, PNG, are included. A total of 180 species are reported. Of the 63 species from PNG 51 are new to the country, and 123 of the 149 species from NC are new to the territory.

  • 40.
    Lind, Olle
    et al.
    Lund University, Sweden.
    Milton, Ida
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Andersson, Elin
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Roth, Lina
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    High visual acuity revealed in dogs2017Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 12, nr 12, artikel-id e0188557Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Humans have selectively bred and used dogs over a period of thousands of years, and more recently the dog has become an important model animal for studies in ethology, cognition and genetics. These broad interests warrant careful descriptions of the senses of dogs. Still there is little known about dog vision, especially what dogs can discriminate in different light conditions. We trained and tested whippets, pugs, and a Shetland sheepdog in a two-choice discrimination set-up and show that dogs can discriminate patterns with spatial frequencies between 5.5 and 19.5 cycle per degree (cpd) in the bright light condition (43 cd m(-2)). This is a higher spatial resolution than has been previously reported although the individual variation in our tests was large. Humans tested in the same set-up reached acuities corresponding to earlier studies, ranging between 32.1 and 44.2 cpd. In the dim light condition (0.0087 cd m(-2)) the acuity of dogs ranged between 1.8 and 3.5 cpd while in humans, between 5.9 and 9.9 cpd. Thus, humans make visual discrimination of objects from roughly a threefold distance compared to dogs in both bright and dim light.

  • 41. Lindholm, Caroline
    Intermittent fasting in chickens: Physiological mechanisms and welfare implications for broiler breeders2019Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Broiler breeder chickens are the parent stock used to produce broiler chickens raised for human consumption and have long been caught in a welfare dilemma. The immensely successful selection of fast-growing meat-type chickens over the last 80 years has created a remarkably efficient meat-producer and given us access to cheap chicken meat but has also created health problems for the animals. These problems especially affect the breeder generation, which must be raised with strict feed restriction to limit weight gain and thus maintain physical health and normal fertility. At the same time, however, feed restriction causes chronic hunger and feeding frustration with reduced animal welfare as a result. In the EU alone 60 million breeders are affected annually and although the problem is well-known within the industry, there is financial incentive to keep selecting for even higher growth potential in broilers, further increasing the problems for broiler breeders.

    Many strategies for reducing the impact of growth restriction on breeder welfare have been suggested and are usually aimed at somehow increasing the amount of feed given at feeding times. This can be done either through adding bulky fibers to the diet or by reducing feeding frequency. In this thesis, focus is on the latter as we explore the effects of intermittent fasting (IF) on the welfare of young broiler breeders as well as wild-type Red Junglefowl. Intermittent fasting, or “skip-a-day” feeding, is supposedly the most common feeding strategy for broiler breeders worldwide but is perceived as welfare-reducing and thus illegal in Sweden and several other European countries. In spite of this, the scientific knowledge of how this type of feeding affects chicken welfare is scarce.

    Assessing the overall effect of IF on breeder welfare is complicated by large variations in both physiological and behavioral parameters between feeding and fasting days, but it does appear that chicken welfare is improved at least on the feeding days of IF regimens. It also seems that some of the health benefits reported from mammalian studies of IF may apply to chickens as well, although behavioral indicators still point to welfare issues unless the level of feed restriction can be relaxed. In comparison with daily feed restriction, IF appears to increase the motivation for feed consumption but to reduce the motivation for appetitive behaviors such as foraging, which may explain why birds fed on this type of schedule are often reported as calmer.

    Delarbeten
    1. Slow and steady wins the race? No signs of reduced welfare in smallerbroiler breeder hens at four weeks of age
    Öppna denna publikation i ny flik eller fönster >>Slow and steady wins the race? No signs of reduced welfare in smallerbroiler breeder hens at four weeks of age
    Visa övriga...
    2015 (Engelska)Ingår i: Animal Welfare, ISSN 0962-7286, Vol. 24, nr 4, s. 447-454Artikel i tidskrift (Refereegranskat) Published
    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.

    Ort, förlag, år, upplaga, sidor
    Universities Federation for Animal Welfare, 2015
    Nyckelord
    animal welfare, broiler breeders, chicken, feed restriction, growth, stress
    Nationell ämneskategori
    Zoologi
    Identifikatorer
    urn:nbn:se:liu:diva-122024 (URN)10.7120/09627286.24.4.447 (DOI)000363898500009 ()
    Anmärkning

    Funding agencies: Swedish research council Formas [2013-293]

    Tillgänglig från: 2015-10-16 Skapad: 2015-10-16 Senast uppdaterad: 2019-10-10
    2. Growth heterogeneity in broiler breeder pullets is settled before the onset of feed restriction but is not predicted by size at hatch
    Öppna denna publikation i ny flik eller fönster >>Growth heterogeneity in broiler breeder pullets is settled before the onset of feed restriction but is not predicted by size at hatch
    Visa övriga...
    2017 (Engelska)Ingår i: Journal of Animal Science, ISSN 0021-8812, E-ISSN 1525-3163, Vol. 95, nr 1, s. 182-193, artikel-id 2017.95Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Uniform growth is a desirable trait in  all large-scale animal production systems because it  simplifies animal management and increases profitability.  In parental broiler flocks, so-called broiler  breeders, low growth uniformity is largely attributed  to the feed competition that arises from quantitatively  restricted feeding. As feed restriction is crucial to  maintaining healthy and fertile breeders, several practices  for reducing feed competition and the associated  growth heterogeneity have been suggested and range  from nutrient dilution by increasing fiber content in  feed to intermittent fasting with increased portion size  (“skip a day”), but no practice appears to be entirely  effective. The fact that a large part of the heterogeneity  remains even when feed competition is minimized  suggests that some growth variation is caused by other  factors. We investigated whether this variation arises  during embryonic development (as measured by size at  hatch) or during posthatch development by following  the growth and body composition of birds of varying  hatch sizes. Our results support the posthatch alternative,  with animals that later grow to be small or large  (here defined as >1 SD lighter or heavier than mean  BW of the flock) being significantly different in size as  early as 1 d after gaining access to feed (P < 0.05). We  then investigated 2 possible causes for different postnatal  growth: that high growth performance is linked 1) to  interindividual variations in metabolism (as measured  by cloacal temperature and verified by respirometry)  or 2) to higher levels of social motivation (as measured  in a social reinstatement T-maze), which should reduce  the stress of being reared in large-scale commercial  flocks. Neither of these follow-up hypotheses could  account for the observed heterogeneity in growth. We  suggest that the basis of growth heterogeneity in broiler  breeder pullets may already be determined at the time  of hatch in the form of qualitatively different maternal  investments or immediately thereafter as an indirect  result of differences in incubation conditions, hatching  time, and resulting fasting time. Although this potential  difference in maternal investment is not seen in body  mass, tarsometatarsal length, or full body length of  day-old chicks arriving at the farm, it may influence  the development of differential feed and water intake  during the first day of feeding, which in turn has direct  effects on growth heterogeneity.

    Ort, förlag, år, upplaga, sidor
    Champaign, IL, United States: American Society of Animal Science, 2017
    Nyckelord
    broiler breeders, feed restriction
    Nationell ämneskategori
    Ekologi
    Identifikatorer
    urn:nbn:se:liu:diva-133189 (URN)10.2527/jas.2016.0929 (DOI)000397115100019 ()28177396 (PubMedID)
    Tillgänglig från: 2016-12-13 Skapad: 2016-12-13 Senast uppdaterad: 2019-10-10Bibliografiskt granskad
    3. The physiological and neuroendocrine correlates of hunger in the Red Junglefowl (Gallus gallus)
    Öppna denna publikation i ny flik eller fönster >>The physiological and neuroendocrine correlates of hunger in the Red Junglefowl (Gallus gallus)
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    2017 (Engelska)Ingår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, artikel-id 17984Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    The ability to regulate food intake is critical to survival. The hypothalamus is central to this regulation, integrating peripheral signals of energy availability. Although our understanding of hunger in rodents is advanced, an equivalent understanding in birds is lacking. In particular, the relationship between peripheral energy indices and hypothalamic hunger peptides, agouti-related protein (AgRP), proopiomelanocortin (POMC) and neuropeptide Y (NPY) is poorly understood. Here, we compare AgRP, POMC and NPY RNA levels in the hypothalamus of Red Junglefowl chicks raised under ad libitum, chronic restriction and intermittent feeding regimens. Hypothalamic gene expression differed between chronically and intermittently restricted birds, confirming that different restriction regimens elicit different patterns of hunger. By assessing the relationship between hypothalamic gene expression and carcass traits, we show for the first time in birds that AgRP and POMC are responsive to fat-related measures and therefore represent long-term energy status. Chronically restricted birds, having lower indices of fat, show elevated hunger according to AgRP and POMC. NPY was elevated in intermittently fasted birds during fasting, suggesting a role as a short-term index of hunger. The different physiological and neuroendocrine responses to quantitative versus temporal feed restriction provide novel insights into the divergent roles of avian hunger neuropeptides.

    Ort, förlag, år, upplaga, sidor
    NATURE PUBLISHING GROUP, 2017
    Nationell ämneskategori
    Annan biologi
    Identifikatorer
    urn:nbn:se:liu:diva-144265 (URN)10.1038/s41598-017-17922-w (DOI)000418562100024 ()29269733 (PubMedID)
    Anmärkning

    Funding Agencies|Swedish research council Formas [2013-293]; Swedish Centre of Excellence in Animal Welfare Science; Carl Tryggers Stiftelse for Vetenskaplig Forskning

    Tillgänglig från: 2018-01-12 Skapad: 2018-01-12 Senast uppdaterad: 2019-10-10
    4. Measuring ketones in the field: rapid and reliable measures of beta-hydroxybutyrate in birds
    Öppna denna publikation i ny flik eller fönster >>Measuring ketones in the field: rapid and reliable measures of beta-hydroxybutyrate in birds
    2019 (Engelska)Ingår i: Ibis, ISSN 0019-1019, E-ISSN 1474-919X, Vol. 161, nr 1, s. 205-210Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Ketone bodies such as beta-hydroxybutyrate are important indicators of metabolic condition in birds and are linked to a suite of ecologically relevant factors including migratory decision-making, hunger level and ectoparasite load. Portable point-of-care (POC) devices designed to measure ketones in humans offer a cheap and easy solution to field physiologists in comparison with previous laboratory methods; however, their accuracy for use in birds has received scant attention. Here, we assessed the accuracy of a POC ketone meter (FreeStyle Precision Neo, Abbott, IL, USA) using samples from intermittently fed Red Junglefowl Gallus gallus. Although the device overestimated ketone levels in comparison with laboratory-derived values, random error was low and laboratory vs. device values correlated well, indicating that the Precision Neo is of sufficient accuracy for use in the field and is a pragmatic choice for avian physiologists.

    Ort, förlag, år, upplaga, sidor
    WILEY, 2019
    Nyckelord
    intermittent feeding; ketosis; point-of-care; Red Junglefowl
    Nationell ämneskategori
    Ekologi
    Identifikatorer
    urn:nbn:se:liu:diva-153969 (URN)10.1111/ibi.12643 (DOI)000454604400018 ()
    Anmärkning

    Funding Agencies|Swedish research council Formas [2013-293]; Swedish Centre of Excellence in Animal Welfare Science; Carl Tryggers Stiftelse for Vetenskaplig Forsknin

    Tillgänglig från: 2019-01-22 Skapad: 2019-01-22 Senast uppdaterad: 2019-10-10
    5. The Quest for Welfare-Friendly Feeding of Broiler Breeders: Effects of Daily vs. 5:2 Feed Restriction Schedules
    Öppna denna publikation i ny flik eller fönster >>The Quest for Welfare-Friendly Feeding of Broiler Breeders: Effects of Daily vs. 5:2 Feed Restriction Schedules
    Visa övriga...
    2018 (Engelska)Ingår i: Poultry Science, ISSN 0032-5791, E-ISSN 1525-3171, Vol. 97, nr 2, s. 368-377Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Restricted feeding of broiler breeders is required for improved long-term health and welfare. Because feeding frustration and hunger are major welfare concerns during rearing, many suggestions have been made to decrease the negative feelings of hunger while maintaining suitable growth rates and reproductive health. Non-daily ("skip-a-day") feeding schedules are commonly used around the world to increase portion sizes at meal times while restricting intake but these practices are prohibited in many countries due to welfare concerns on fasting days. We compared birds raised on a non-daily feeding schedule (2 non-consecutive fasting days per week, 5:2), previously suggested as a welfare-friendlier non-daily alternative, to birds raised on daily feed restriction. We found signs of increased physiological stress levels in 5:2 birds, including elevated heterophil to lymphocyte ratios (1.00 for 5:2 vs. 0.75 for daily fed at 12 weeks of age), increased adiposity (0.21% lean body weight [LBW] for 5:2 vs. 0.13% LBW for daily fed), and reduced muscle growth (pectoral muscle 5.94% LBW for 5: 2 vs. 6.52% LBW for daily fed). At the same time, 5:2 birds showed signs of lower anxiety before feeding times (activity was reduced from 10.30 in daily fed to 4.85) which may be a result of the lower feed competition associated with larger portion sizes. Although we found no difference in latency to first head movement in tonic immobility between the treatments (136.5 s on average for both groups), 5:2 birds generally showed more interest in a novel object in the home pen which indicated increased risk taking and reduced fear while fasting. The 5:2 birds in this study showed no signs of learning the feeding schedule, and this unpredictability may also increase stress. Taken together, the effects of 5:2 vs. daily feed restriction on the welfare of broiler breeder pullets remain inconclusive and differ between feeding and fasting days. In addition to reducing stress by minimizing the number of fasting days, we suggest that a shift to more predictable schedules may help improve the welfare of broiler breeder pullets.

    Ort, förlag, år, upplaga, sidor
    OXFORD UNIV PRESS, 2018
    Nyckelord
    animal welfare; broiler breeders; feed restriction; intermittent fasting; skip-a-day
    Nationell ämneskategori
    Zoologi
    Identifikatorer
    urn:nbn:se:liu:diva-145242 (URN)10.3382/ps/pex326 (DOI)000424248600003 ()29182752 (PubMedID)
    Anmärkning

    Funding Agencies|Swedish research council Formas [2013-293]; Swedish Centre of Excellence in Animal Welfare Science

    Tillgänglig från: 2018-02-21 Skapad: 2018-02-21 Senast uppdaterad: 2019-10-10
  • 42.
    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.

  • 43.
    Lindholm, Caroline
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Johansson, A.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Middelkoop, A.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Lees, John
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Yngwe, N.
    SweHatch AB, Sweden.
    Berndtson, E.
    SweHatch AB, Sweden.
    Cooper, G.
    Univ Manchester, England.
    Altimiras, Jordi
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    The Quest for Welfare-Friendly Feeding of Broiler Breeders: Effects of Daily vs. 5:2 Feed Restriction Schedules2018Ingår i: Poultry Science, ISSN 0032-5791, E-ISSN 1525-3171, Vol. 97, nr 2, s. 368-377Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Restricted feeding of broiler breeders is required for improved long-term health and welfare. Because feeding frustration and hunger are major welfare concerns during rearing, many suggestions have been made to decrease the negative feelings of hunger while maintaining suitable growth rates and reproductive health. Non-daily ("skip-a-day") feeding schedules are commonly used around the world to increase portion sizes at meal times while restricting intake but these practices are prohibited in many countries due to welfare concerns on fasting days. We compared birds raised on a non-daily feeding schedule (2 non-consecutive fasting days per week, 5:2), previously suggested as a welfare-friendlier non-daily alternative, to birds raised on daily feed restriction. We found signs of increased physiological stress levels in 5:2 birds, including elevated heterophil to lymphocyte ratios (1.00 for 5:2 vs. 0.75 for daily fed at 12 weeks of age), increased adiposity (0.21% lean body weight [LBW] for 5:2 vs. 0.13% LBW for daily fed), and reduced muscle growth (pectoral muscle 5.94% LBW for 5: 2 vs. 6.52% LBW for daily fed). At the same time, 5:2 birds showed signs of lower anxiety before feeding times (activity was reduced from 10.30 in daily fed to 4.85) which may be a result of the lower feed competition associated with larger portion sizes. Although we found no difference in latency to first head movement in tonic immobility between the treatments (136.5 s on average for both groups), 5:2 birds generally showed more interest in a novel object in the home pen which indicated increased risk taking and reduced fear while fasting. The 5:2 birds in this study showed no signs of learning the feeding schedule, and this unpredictability may also increase stress. Taken together, the effects of 5:2 vs. daily feed restriction on the welfare of broiler breeder pullets remain inconclusive and differ between feeding and fasting days. In addition to reducing stress by minimizing the number of fasting days, we suggest that a shift to more predictable schedules may help improve the welfare of broiler breeder pullets.

  • 44.
    Maklakov, Alexei A.
    et al.
    Uppsala University, Sweden.
    Friberg, Urban
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Ageing: Why Males Curtail the Longevity of Their Mates2016Ingår i: Current Biology, ISSN 0960-9822, E-ISSN 1879-0445, Vol. 26, nr 20, s. R929-R932Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    Male nematodes secrete pheromones that accelerate the somatic senescence of potential mates. A new study shows that this harm most likely is an unintended by-product of the males aim to speed up sexual maturation and delay reproductive senescence of future partners.

  • 45.
    Möhlmann, Tim
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Teoretisk Biologi. Linköpings universitet, Tekniska fakulteten. Wageningen Univ and Res, Netherlands.
    Bekendam, A. M.
    Wageningen Univ and Res, Netherlands.
    van Kemenade, I.
    Wageningen Univ and Res, Netherlands.
    Wennergren, Uno
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Teoretisk Biologi. Linköpings universitet, Tekniska fakulteten.
    Favia, G.
    Univ Camerino, Italy.
    Takken, W.
    Wageningen Univ and Res, Netherlands.
    Koenraadt, C. J. M.
    Wageningen Univ and Res, Netherlands.
    Latitudinal diversity of biting midge species within the Obsoletus group across three habitats in Europe2019Ingår i: Medical and Veterinary Entomology, ISSN 0269-283X, E-ISSN 1365-2915, Vol. 33, nr 3, s. 420-426Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Culicoides species from the Obsoletus group are important vectors of bluetongue and Schmallenberg virus. This group consists of several species that cannot easily be identified using morphological characteristics. Therefore, limited information is available about their distribution and habitat preferences. In this study, we aimed to elucidate the species composition of the Obsoletus group in three habitat types at climatically different latitudes across Europe. Traps were placed in three habitat types in three countries at different latitudes. After DNA extraction, biting midges were identified using PCR and gel electrophoresis. Extraction of DNA using Chelex proved to be a cost and time efficient method for species identification. A latitudinal effect on the relative abundance of species from the Obsoletus group was found. Species composition was unique for most country-habitat combinations. The majority of biting midges were either C. obsoletus s.s. or C. scoticus, and both species were found at all latitudes and habitats. Their wide distribution and their high abundance at livestock farms make these species likely candidates for rapid farm-to-farm transmission of pathogens throughout Europe. Our results emphasize the need to differentiate Obsoletus group species to better understand their ecology and contribution to pathogen transmission.

  • 46.
    Möhlmann, Tim
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Teoretisk Biologi. Linköpings universitet, Tekniska fakulteten. Wageningen University of and Research Centre, Netherlands.
    Wennergren, Uno
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Teoretisk Biologi. Linköpings universitet, Tekniska fakulteten.
    Tälle, Malin
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Teoretisk Biologi. Linköpings universitet, Tekniska fakulteten.
    Favia, Guido
    University of Camerino, Italy.
    Damiani, Claudia
    University of Camerino, Italy.
    Bracchetti, Luca
    University of Camerino, Italy.
    Koenraadt, Constantianus J. M.
    Wageningen University of and Research Centre, Netherlands.
    Community analysis of the abundance and diversity of mosquito species (Diptera: Culicidae) in three European countries at different latitudes2017Ingår i: Parasites & Vectors, ISSN 1756-3305, E-ISSN 1756-3305, Vol. 10, artikel-id 510Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Studies on mosquito species diversity in Europe often focus on a specific habitat, region or country. Moreover, different trap types are used for these sampling studies, making it difficult to compare and validate results across Europe. To facilitate comparisons of trapping sites and community analysis, the present study used two trap types for monitoring mosquito species diversity in three habitat types for three different countries in Europe. Methods: Mosquitoes were trapped using Biogents Sentinel (BGS), and Mosquito Magnet Liberty Plus (MMLP) traps at a total of 27 locations in Sweden, the Netherlands and Italy, comprising farm, peri-urban and wetland habitats. From July 2014 to June 2015 all locations were sampled monthly, except for the winter months. Indices of species richness, evenness and diversity were calculated, and community analyses were carried out with non-metric multidimensional scaling (NMDS) techniques. Results: A total of 11,745 female mosquitoes were trapped during 887 collections. More than 90% of the mosquitoes belonged to the genera Culex and Aedes, with Culex pipiens being the most abundant species. The highest mosquito diversity was found in Sweden. Within Sweden, species diversity was highest in wetland habitats, whereas in the Netherlands and Italy this was highest at farms. The NMDS analyses showed clear differences in mosquito communities among countries, but not among habitat types. The MMLP trapped a higher diversity of mosquito species than the BGS traps. Also, MMLP traps trapped higher numbers of mosquitoes, except for the genera Culex and Culiseta in Italy. Conclusions: A core mosquito community could be identified for the three countries, with Culex pipiens as the most abundant species. Differences in mosquito species communities were more defined by the three countries included in the study than by the three habitat types. Differences in mosquito community composition across countries may have implications for disease emergence and further spread throughout Europe. Future research should, therefore, focus on how field data of vector communities can be incorporated into models, to better assess the risk of mosquito-borne disease outbreaks.

  • 47.
    Möhlmann, Tim
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Teoretisk Biologi. Linköpings universitet, Tekniska fakulteten. Wageningen Univ and Res, Netherlands.
    Wennergren, Uno
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Teoretisk Biologi. Linköpings universitet, Tekniska fakulteten.
    Tälle, Malin
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Teoretisk Biologi. Linköpings universitet, Tekniska fakulteten.
    Favia, Guido
    Univ Camerino, Italy.
    Damiani, Claudia
    Univ Camerino, Italy.
    Bracchetti, Luca
    Univ Camerino, Italy.
    Takken, Willem
    Wageningen Univ and Res, Netherlands.
    Koenraadt, Constantianus J. M.
    Wageningen Univ and Res, Netherlands.
    Community analysis of the abundance and diversity of biting midge species (Diptera: Ceratopogonidae) in three European countries at different latitudes2018Ingår i: Parasites & Vectors, ISSN 1756-3305, E-ISSN 1756-3305, Vol. 11, artikel-id 217Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: The outbreaks of bluetongue and Schmallenberg disease in Europe have increased efforts to understand the ecology of Culicoides biting midges and their role in pathogen transmission. However, most studies have focused on a specific habitat, region, or country. To facilitate wider comparisons, and to obtain a better understanding of the spread of disease through Europe, the present study focused on monitoring biting midge species diversity in three different habitat types and three countries across Europe. Methods: Biting midges were trapped using Onderstepoort Veterinary Institute light traps at a total of 27 locations in Sweden, the Netherlands and Italy, comprising farm, peri-urban and wetland habitats. From July 2014 to June 2015 all locations were sampled monthly, except for during the winter months. Trapped midges were counted and identified morphologically. Indices on species richness, evenness and diversity were calculated. Community compositions were analysed using non-metric multidimensional scaling (NMDS) techniques. Results: A total of 50,085 female midges were trapped during 442 collection nights. More than 88% of these belonged to the Obsoletus group. The highest midge diversity was found in Sweden, while species richness was highest in the Netherlands, and most specimens were trapped in Italy. For habitats within countries, diversity of the trapped midges was lowest for farms in all countries. Differences in biting midge species communities were more distinct across the three countries than the three habitat types. Conclusions: A core midge community could be identified, in which the Obsoletus group was the most abundant. Variations in vector communities across countries imply different patterns of disease spread throughout Europe. How specific species and their associated communities affect disease risk is still unclear. Our results emphasize the importance of midge diversity data at community level, how this differs across large geographic range within Europe, and its implications on assessing risks of midge-borne disease outbreaks.

  • 48.
    Nespolo, Roberto F.
    et al.
    University of Austral Chile, Chile; University of Catolica Chile, Chile.
    Gonzalez-Lagos, Cesar
    University of Catolica Chile, Chile; University of Bernardo OHiggins, Chile.
    Solano-Iguaran, Jaiber J.
    University of Austral Chile, Chile.
    Elfwing, Magnus
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska fakulteten.
    Garitano-Zavala, Alvaro
    University of Mayor San Andres, Bolivia.
    Manosa, Santiago
    University of Barcelona, Spain.
    Carlos Alonso, Juan
    CSIC, Spain.
    Altimiras, Jordi
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Aerobic power and flight capacity in birds: a phylogenetic test of the heart-size hypothesis2018Ingår i: Journal of Experimental Biology, ISSN 0022-0949, E-ISSN 1477-9145, Vol. 221, nr 1, artikel-id UNSP jeb175208Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Flight capacity is one of the most important innovations in animal evolution; it only evolved in insects, birds, mammals and the extinct pterodactyls. Given that powered flight represents a demanding aerobic activity, an efficient cardiovascular system is essential for the continuous delivery of oxygen to the pectoral muscles during flight. It is well known that the limiting step in the circulation is stroke volume (the volume of blood pumped from the ventricle to the body during each beat), which is determined by the size of the ventricle. Thus, the fresh mass of the heart represents a simple and repeatable anatomical measure of the aerobic power of an animal. Although several authors have compared heart masses across bird species, a phylogenetic comparative analysis is still lacking. By compiling heart sizes for 915 species and applying several statistical procedures controlling for body size and/or testing for adaptive trends in the dataset (e.g. model selection approaches, phylogenetic generalized linear models), we found that (residuals of) heart size is consistently associated with four categories of flight capacity. In general, our results indicate that species exhibiting continuous hovering flight (i.e. hummingbirds) have substantially larger hearts than other groups, species that use flapping flight and gliding show intermediate values, and that species categorized as poor flyers show the smallest values. Our study reveals that on a broad scale, routine flight modes seem to have shaped the energetic requirements of birds sufficiently to be anatomically detected at the comparative level.

  • 49.
    Nicklasson, Sandra
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Sjöström, Desirée
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Amundin, Mats
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten. Kolmården Wildlife Park, Kolmården, Sweden.
    Roth, Daniel
    Borås Zoo, Borås, Sweden.
    Hernandez Salazar, Laura Teresa
    Instituto de Neuro-Etologia, Universidad Veracruzana, Xalapa, Veracruz, Mexico.
    Laska, Matthias
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Taste responsiveness to two steviol glycosides in three species of nonhuman primates2018Ingår i: Current Zoology, ISSN 1674-5507, Vol. 64, nr 1, s. 63-68Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Primates have been found to differ widely in their taste perception and studies suggest that a co-evolution between plant species bearing a certain taste substance and primate species feeding on these plants may contribute to such between-species differences. Considering that only platyrrhine primates, but not catarrhine or prosimian primates, share an evolutionary history with the neotropical plant Stevia rebaudiana, we assessed whether members of these three primate taxa differ in their ability to perceive and/or in their sensitivity to its two quantitatively predominant sweet-tasting substances. We found that not only neotropical black-handed spider monkeys, but also paleotropical black-and-white ruffed lemurs and Western chimpanzees are clearly able to perceive stevioside and rebaudioside A. Using a two-bottle preference test of short duration, we found that Ateles geoffroyi preferred concentrations as low as 0.05 mM stevioside and 0.01 mM rebaudioside A over tap water. Taste preference thresholds of Pan troglodytes were similar to those of the spider monkeys, with 0.05 mM for stevioside and 0.03 mM for rebaudioside A, whereas Varecia variegata was slightly less sensitive with a threshold value of 0.1 mM for both substances. Thus, all three primate species are, similar to human subjects, clearly more sensitive to both steviol glycosides compared to sucrose. Only the spider monkeys displayed concentration-response curves with both stevioside and rebaudioside A which can best be described as an inverted U-shaped function suggesting that Ateles geoffroyi, similar to human subjects, may perceive a bitter side taste at higher concentrations of these substances. Taken together, the results of the present study do not support the notion that a co-evolution between plant and primate species may account for between-species differences in taste perception of steviol glycosides.

  • 50.
    Norlen, Ellen
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Sjöström, Desiree
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Hjelm, Madeleine
    Borås Zoo, Sweden.
    Hard, Therese
    Borås Zoo, Sweden.
    Laska, Matthias
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska fakulteten.
    Taste responsiveness of Western chimpanzees (Pan troglodytes verus) to five food-associated saccharides2019Ingår i: Primates, ISSN 0032-8332, E-ISSN 1610-7365, Vol. 60, nr 1, s. 29-39Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Using a two-bottle choice test of short duration, we determined taste preference thresholds for sucrose, fructose, glucose, lactose, and maltose in three Western chimpanzees (Pan troglodytes verus). Further, we assessed relative preferences for these five saccharides when presented at equimolar concentrations and determined taste preference difference thresholds for sucrose, that is, the smallest concentration difference at which the chimpanzees display a preference for one of the two options. We found that the chimpanzees significantly preferred concentrations as low as 20mM sucrose, 40mM fructose, and 80mM glucose, lactose, and maltose over tap water. When given a choice between all binary combinations of these five saccharides presented at equimolar concentrations of 100, 200, and 400mM, respectively, the animals displayed significant preferences for individual saccharides in the following order: sucroseamp;gt;fructoseamp;gt;glucose=maltose=lactose. The taste difference threshold for sucrose, expressed as Weber ratio (I/I), was 0.3 and 0.4, respectively, at reference concentrations of 100 and 200mM. The taste sensitivity of the chimpanzees to the five saccharides falls into the same range found in other primate species. Remarkably, their taste preference thresholds are similar, and with two saccharides even identical, to human taste detection thresholds. The pattern of relative taste preferences displayed by the chimpanzees was similar to that found in platyrrhine primates and to the pattern of relative sweetness as reported by humans. Taken together, the results of the present study are in line with the notion that taste sensitivity for food-associated carbohydrates may correlate positively with phylogenetic relatedness. Further, they support the notion that relative preferences for food-associated carbohydrates, but not taste difference thresholds, may correlate with dietary specialization in primates.

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