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  • 51.
    Hellstrom, Anders R
    et al.
    Uppsala University.
    Sundstrom, Elisabeth
    Swedish University Agriculture Science.
    Gunnarsson, Ulrika
    Uppsala University.
    BedHom, Bertrand
    AgroParisTech.
    Tixier-Boichard, Michele
    AgroParisTech.
    Honaker, Christa F
    Virginia Polytech Institute and State University.
    Sahlqvist, Anna-Stina
    Uppsala University.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Siegel, Paul B
    Virginia Polytech Institute and State University.
    Kerje, Susanne
    Uppsala University.
    Andersson, Leif
    Uppsala University.
    Sex-linked barring in chickens is controlled by the CDKN2A/B tumour suppressor locus2010Ingår i: PIGMENT CELL and MELANOMA RESEARCH, ISSN 1755-1471, Vol. 23, nr 4, s. 521-530Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Sex-linked barring, a common plumage colour found in chickens, is characterized by black and white barred feathers. Previous studies have indicated that the white bands are caused by an absence of melanocytes in the feather follicle during the growth of this region. Here, we show that Sex-linked barring is controlled by the CDKN2A/B locus, which encodes the INK4b and ARF transcripts. We identified two non-coding mutations in CDKN2A that showed near complete association with the phenotype. In addition, two missense mutations were identified at highly conserved sites, V9D and R10C, and every bird tested with a confirmed Sex-linked barring phenotype carried one of these missense mutations. Further work is required to determine if one of these or a combined effect of two or more CDKN2A mutations is causing Sex-linked barring. This novel finding provides the first evidence that the tumour suppressor locus CDKN2A/B can affect pigmentation phenotypes and sheds new light on the functional significance of this gene.

  • 52.
    Hernández Salazar, Laura T.
    et al.
    Instituto de Neuroetologia, Universidad Veracruzana , Xalapa , Veracruz 91000 , Mexico.
    Dominy, Nathaniel J.
    Department of Anthropology , Dartmouth College , Hanover , NH 03755 , USA.
    Laska, Matthias
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi.
    The Sensory Systems of Alouatta : Evolutionwith an Eye to Ecology2015Ingår i: Howler Monkeys: Adaptive Radiation, Systematics, and Morphology / [ed] Martín M. Kowalewski et al., New York: Springer Science+Business Media B.V., 2015, s. 317-336Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    Our knowledge about the perceptual world of howler monkeys is unevenlydistributed between the fi ve senses. Whereas there is abundant knowledge about thesense of vision in the genus Alouatta , only limited data on the senses of hearing,smell, taste, and touch are available. The discovery that howler monkeys are theonly genus among the New World primates to possess routine trichromacy hasimportant implications for the evolution of color vision and therefore has been studiedintensively. Detailed information about the genetic mechanisms and physiologicalprocesses underlying color vision in howler monkeys are available. Although thesound production, vocal repertoire, and acoustic communication in the genusAlouatta have been well documented, basic physiological measures of hearing performancesuch as audiograms are missing. Similarly, despite an increasing numberof observational studies on olfactory communication in howler monkeys, there is acomplete lack of physiological studies on the effi ciency of their sense of smell.Information about the senses of taste and touch is even scarcer and mainly restrictedto a description of their anatomical basis. A goal of this chapter is to summarize ourcurrent knowledge of the anatomy, physiology, genetics, and behavioral relevanceof the different senses in howler monkeys in comparison to other platyrrhines.

  • 53.
    Håkansson, Jennie
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Behavioural aspects of conservation breeding: Red junglefowl (Gallus gallus) as a case study2007Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Ett stort antal utrotningshotade djurarter ingår idag i bevarandeprogram världen över. Små populationer hålls då i skyddade miljöer, exempelvis i djurparker, och i många fall är målet att återintroducera djur till naturen. Dessvärre är det vanligt att det uppstår problem när djur återintroduceras vilket kan bero på beteendemässiga anpassningar som uppkommit under tiden i fångenskap. Syftet med den här studien var därför att undersöka beteendemässiga aspekter på bevarandeavel och försöka ta reda på om och hur djur påverkas beteendemässigt av att hållas i skyddade fångenskapsmiljöer. I projektet användes röda djungelhöns (Gallus gallus) som en fallstudie. En granskning av beteendevariation mellan olika populationer av röda djungelhöns i fångenskap konstaterade skillnader i antipredatorbeteende, socialt beteende och födosöksbeteende. Vid en genetisk studie av samma populationer upptäcktes dessutom ett samband mellan genetisk diversitet och beteendevariation som potentiellt kan vara intressant ur ett bevarandeperspektiv. Socialt beteende, födosöksbeteende och olika aspekter av rädsla studerades vidare i populationer med olika bakgrund som fick växa upp tillsammans i en grupp. Resultaten visade att populationerna bara skilde sig åt i rädslebeteenden vilket antyder att denna typ av beteende i större utsträckning påverkas av långvarig avel i en viss fångenskapsmiljö medan socialt beteende och födosöksbeteende istället kan bero på den omedelbara sociala eller fysiska miljön. Antipredatorbeteende studerades också i en longitudinell studie av två populationer över fyra generationer och det visade sig att populationerna blev mer lika varandra ju längre tiden gick då de hölls under likadana miljöförhållanden. Det verkar alltså som om antipredatorbeteende kan förändras av avel i en viss miljö efter bara ett fåtal generationer. Utöver detta studerades även dagliga beteendemönster i olika djurparksmiljöer samt dygnsrytm av galanden hos både vilda populationer och djurparkspopulationer inom artens naturliga utbredningsområde. Resultaten tyder på att sådana beteendemönster inte påverkas nämnvärt av att djur hålls i fångenskap. Fallstudien som presenteras här är ett av de första försöken att, ur ett bevarandeperspektiv, studera hur fångenskapsmiljöer kan påverka djurs beteende och resultaten talar för att dessa aspekter är viktiga att ta hänsyn till vid planering av bevarandeavel.

    Delarbeten
    1. Behavioural and morphological variation between captive populations of red junglefowl (Gallus gallus) - possible implications for conservation
    Öppna denna publikation i ny flik eller fönster >>Behavioural and morphological variation between captive populations of red junglefowl (Gallus gallus) - possible implications for conservation
    2005 (Engelska)Ingår i: Biological Conservation, ISSN 0006-3207, Vol. 122, nr 3, s. 431-439Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    The escalating threats to ecosystems worldwide have lead to a need for efficient methods to breed animals in captivity and to prepare captive-born animals for release back to the wild. However, life in captivity may lead to modifications in the animal’s behaviour mainly by genetic changes, including behavioural adaptations such as reduced predator responses. Such modifications may seriously affect survival after a reintroduction. The present study was a first screening of behavioural and morphological variation between different captive populations in standardized test situations using red junglefowl as a model species. The birds were tested in three different test situations in order to measure anti-predatory behaviour, social behaviour and exploratory behaviour. The results of this study clearly show that there are behavioural differences between the captive populations which potentially can be crucial for the animals in a reintroduction situation. However, the extent to which these differences are due to genetic changes caused by small breeding populations or adaptations to the different captive environments is not yet known, although morphological differences found suggest that genetic variation may cause some of the behavioural differences as well. The differences found imply that life in captivity can affect an animal’s behaviour and even though the red junglefowl is merely used as a model here, this suggests that these aspects may be important to consider also in other species where reintroduction is a more central motive for keeping the animals in captivity.

    Nyckelord
    Behaviour; Conservation; Captive breeding; Red junglefowl; Gallus gallus
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-12648 (URN)10.1016/j.biocon.2004.09.004 (DOI)
    Tillgänglig från: 2007-10-19 Skapad: 2007-10-19 Senast uppdaterad: 2013-11-06
    2. Genetic diversity and its correlation with behavioural variance in captive populations of red junglefowl - possible implications for conservation
    Öppna denna publikation i ny flik eller fönster >>Genetic diversity and its correlation with behavioural variance in captive populations of red junglefowl - possible implications for conservation
    Visa övriga...
    2010 (Engelska)Manuskript (preprint) (Övrigt vetenskapligt)
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-12649 (URN)
    Tillgänglig från: 2007-10-19 Skapad: 2007-10-19 Senast uppdaterad: 2015-10-05Bibliografiskt granskad
    3. Behavioural differences between two captive populations of red junglefowl (Gallus gallus) with different genetic background, raised under identical conditions
    Öppna denna publikation i ny flik eller fönster >>Behavioural differences between two captive populations of red junglefowl (Gallus gallus) with different genetic background, raised under identical conditions
    2007 (Engelska)Ingår i: Applied Animal Behaviour Science, ISSN 0168-1591, E-ISSN 1872-9045, Vol. 102, nr 1-2, s. 24-38Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Ex situ conservation of threatened species may lead to behavioural adaptation, which can affect success of reintroduction attempts. In previous studies, we investigated the effects of captivity on the behaviour of red jungle fowl (Gallus gallus) and found that captive populations differed behaviourally as well as genetically. The aim of the present study was to compare the behaviour of two of the previously studied populations, raised under identical conditions. Eggs were collected from birds at Copenhagen zoo (Cop) and Götala research station (Got) and were incubated and hatched together. Twenty-eight birds (16 Got and 12 Cop) were reared together and tested in eight different behavioural tests, measuring different aspects of fear-related behaviours as well as exploratory and social behaviours. The study revealed several differences in fear-related behaviours between the populations but none in exploratory or social behaviours. In general, one of the populations (Cop) showed more intense fear behaviours than the other (Got), which instead were less fearful in their behaviours. This indicates that breeding animals in captivity may lead to behavioural modifications, which can affect the outcome of reintroductions. The results further suggest that fear-related behaviours are dependent on the genetic background of the animals while social behaviours may be more influenced by the social environment. Since fear-related behaviours, such as predator avoidance and fear of humans, are essential for a life in the wild, these aspects are crucial for the breeding of animals in captivity for conservation purposes.

    Nyckelord
    Behaviour, Captive breeding, Conservation, Gallus gallus, Red jungle fowl
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-12650 (URN)10.1016/j.applanim.2006.03.013 (DOI)
    Tillgänglig från: 2007-10-19 Skapad: 2007-10-19 Senast uppdaterad: 2017-12-14
    4. A longitudinal study of antipredator behaviour in four successive generations of two populations of captive red junglefowl
    Öppna denna publikation i ny flik eller fönster >>A longitudinal study of antipredator behaviour in four successive generations of two populations of captive red junglefowl
    2008 (Engelska)Ingår i: Applied Animal Behaviour Science, ISSN 0168-1591, E-ISSN 1872-9045, Vol. 114, nr 3-4, s. 409-418Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Conservation breeding and reintroduction into the wild can only be an effective management tool if behaviours essential for a life in the wild are maintained in captivity. The aim of this study was to investigate how a protected captive environment influences antipredator behaviour over generations. The red junglefowl (Gallus gallus) was used as a case study. Birds from two different captive populations were followed over four generations. In the last three generations, all birds were hatched and reared in the same indoor settings. Antipredator behaviour was measured in each generation in a standardised test where the birds were exposed to a simulated predator attack. The test was divided into three parts: pre-exposure period, exposure and post-exposure periods. There was an interaction effect between Population and generation (F-3.129 = 4.84, P < 0.01) on behaviour during the pre-exposure period, suggesting that the birds "baseline" agitation level may have been altered differently in the two populations. Population differences were also found during the post-exposure period but the populations tended to become more similar over successive generations in their behaviour after the exposure. Furthermore, there were significant effects of generation (H (d.f. = 1, N = 137) = 10.94, P < 0.05) as well as population (H (d.f. = 1, N = 137) = 5.17, P < 0.05) on the immediate reaction to the simulated predator attack. In conclusion, over four successive generations, the two populations altered their antipredator behaviour and tended to become more similar. This study shows that antipredator behaviour may change over generations in a captive environment. This is likely to be one of the most crucial factors for successful reintroduction into the wild and hence, it is a very important aspect to consider for conservation breeding.

    Nyckelord
    Domestication, Contrafreeloading, Junglefowl, White Leghorn, Age, Social isolation
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-16126 (URN)10.1016/j.applanim.2008.04.003 (DOI)
    Tillgänglig från: 2009-01-08 Skapad: 2009-01-07 Senast uppdaterad: 2017-12-14Bibliografiskt granskad
    5. Behavioural sex differences and diurnal crowing rhythms in red junglefowl (Gallus gallus) in Northern India
    Öppna denna publikation i ny flik eller fönster >>Behavioural sex differences and diurnal crowing rhythms in red junglefowl (Gallus gallus) in Northern India
    2010 (Engelska)Artikel i tidskrift (Refereegranskat) Submitted
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-12652 (URN)
    Tillgänglig från: 2007-10-19 Skapad: 2007-10-19 Senast uppdaterad: 2010-04-20
  • 54.
    Håkansson, Jennie
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Behavioural differences and genetic relationships between four captive populations of red junglefowl (Gallus gallus): possible implications for conservation2005Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Bevarande av utrotningshotade djur sker idag i stor utsträckning i samarbete med djurparker. Målet med sådana s.k. ex situ-bevarandeprogram är att så småningom återintroducera djur till naturen för att skydda arten från utrotning. Återintroduktioner har dock visat sig vara problematiska i många fall. Att hålla djur i fångenskap kan leda till beteendemässiga förändringar till följd av anpassning till den skyddade miljön, förändrade selektionstryck och förlust av genetisk variation. Detta skulle kunna förklara en del av de misslyckade återintroduktionerna och för att bevarandeprogrammen ska bli effektivare krävs mer kunskap om vad som sker när djur placeras fångenskap. Det övergripande syftet med den här studien var därför att undersöka beteendemässiga och genetiska aspekter på ex situ-bevarande samt att utreda om hållandet av små djurpopulationer i fångenskap kan leda till förändringar som kan påverka framgången av en återintroducering. Röda djungelhöns (Gallus gallus) användes som modell för att kunna undersöka detta. I artikel I studerades beteendeskillnader mellan fyra populationer av röda djungelhöns. Hönsen studerades i olika testsituationer för att mäta antipredatorbeteende, socialt beteende och utforskningsbeteende. Resultaten visade klara skillnader i beteende mellan de olika populationerna och flera av dessa är relevanta utifrån ett bevarandeperspektiv. I artikel II analyserades det genetiska förhållandet mellan populationerna med hjälp av mikrosatellitmarkörer och möjliga samband med resultaten från artikel I undersöktes. Resultaten visade att populationerna var genetiskt differentierade och att de inom varje population hade förlorat en stor del av sin ursprungliga genetiska diversitet. När resultaten från de två artiklarna jämfördes visade det sig dessutom att den genetiska diversiteten följde samma mönster som rankingen av beteendemässig variation. De populationer med mest genetisk variation var också de som visade mest beteendemässig variation. Resultaten från artikel I och II antyder att hållande av djur i exempelvis djurparker kan påverka djuren både beteendemässigt och genetiskt. Röda djungelhöns användes här som en modell men resultaten tyder på att det här är viktigt att tänka på även hos arter där återintroducering är ett mer centralt motiv för att hålla djuren i fångenskap.

    Delarbeten
    1. Behavioural and morphological variation between captive populations of red junglefowl (Gallus gallus) - possible implications for conservation
    Öppna denna publikation i ny flik eller fönster >>Behavioural and morphological variation between captive populations of red junglefowl (Gallus gallus) - possible implications for conservation
    2005 (Engelska)Ingår i: Biological Conservation, ISSN 0006-3207, Vol. 122, nr 3, s. 431-439Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    The escalating threats to ecosystems worldwide have lead to a need for efficient methods to breed animals in captivity and to prepare captive-born animals for release back to the wild. However, life in captivity may lead to modifications in the animal’s behaviour mainly by genetic changes, including behavioural adaptations such as reduced predator responses. Such modifications may seriously affect survival after a reintroduction. The present study was a first screening of behavioural and morphological variation between different captive populations in standardized test situations using red junglefowl as a model species. The birds were tested in three different test situations in order to measure anti-predatory behaviour, social behaviour and exploratory behaviour. The results of this study clearly show that there are behavioural differences between the captive populations which potentially can be crucial for the animals in a reintroduction situation. However, the extent to which these differences are due to genetic changes caused by small breeding populations or adaptations to the different captive environments is not yet known, although morphological differences found suggest that genetic variation may cause some of the behavioural differences as well. The differences found imply that life in captivity can affect an animal’s behaviour and even though the red junglefowl is merely used as a model here, this suggests that these aspects may be important to consider also in other species where reintroduction is a more central motive for keeping the animals in captivity.

    Nyckelord
    Behaviour; Conservation; Captive breeding; Red junglefowl; Gallus gallus
    Nationell ämneskategori
    Naturvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-12648 (URN)10.1016/j.biocon.2004.09.004 (DOI)
    Tillgänglig från: 2007-10-19 Skapad: 2007-10-19 Senast uppdaterad: 2013-11-06
    2. Genetic relationships between captive populations of red junglefown (Gallus gallus) determined by microsatellite analysis - possible implications for conservation
    Öppna denna publikation i ny flik eller fönster >>Genetic relationships between captive populations of red junglefown (Gallus gallus) determined by microsatellite analysis - possible implications for conservation
    Visa övriga...
    (Engelska)Manuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Animals are often kept in captivity for conservation purposes. However, maintenance in captivity can affect the animals by, for example, altered selection pressures, adaptations to the captive environment and loss of genetic variation. This may cause behavioural modifications which could explain some of the difficulty which reintroductions have encountered in the past. The aim of the present study was to examine the genetic relationships between four captive populations of red junglefowl (Gallus gallus) which have been shown to behave differently in test situations (Håkansson and Jensen, 2005). We also intended to explore possible correlations between genetic relationships and the behavioural differences found. For this investigation, we used 21 microsatellite markers distributed throughout the genome. In accordance with our hypothesis, the results showed that the populations were genetically differentiated. For example, across all populations, FST equalled to 0.304 which indicates strong population differentiation and in the assignment test, all individuals were correctly assigned to their population of origin. Regarding genetic variation, it was evident that the populations had lost a considerable amount of their assumed original genetic variation. Genetic diversity within populations as measured by He spanned from 0.34 to 0.48. Interestingly, the ranking of genetic variation within each population followed the same pattern as the ranking of behavioural variation. The study indicates that keeping animals in captivity can lead to major changes in genotype and behaviour even though the motive is maintenance rather than domestication. This may affect the animals' ability to cope with new situations and these issues are therefore very important to consider when breeding animals in captivity for conservation purposes.

    Nyckelord
    Conservation breeding, Gallus gallus, Genetic differentiation, Microsatellites, Red junglefowl
    Nationell ämneskategori
    Teknik och teknologier
    Identifikatorer
    urn:nbn:se:liu:diva-100401 (URN)
    Tillgänglig från: 2013-11-06 Skapad: 2013-11-06 Senast uppdaterad: 2013-11-06
  • 55.
    Håkansson, Jennie
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Ahlander, Susanne
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Behavioural sex differences and diurnal crowing rhythms in red junglefowl (Gallus gallus) in Northern India2010Artikel i tidskrift (Refereegranskat)
  • 56.
    Håkansson, Jennie
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Bratt, Carl
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Behavioural differences between two captive populations of red junglefowl (Gallus gallus) with different genetic background, raised under identical conditions2007Ingår i: Applied Animal Behaviour Science, ISSN 0168-1591, E-ISSN 1872-9045, Vol. 102, nr 1-2, s. 24-38Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Ex situ conservation of threatened species may lead to behavioural adaptation, which can affect success of reintroduction attempts. In previous studies, we investigated the effects of captivity on the behaviour of red jungle fowl (Gallus gallus) and found that captive populations differed behaviourally as well as genetically. The aim of the present study was to compare the behaviour of two of the previously studied populations, raised under identical conditions. Eggs were collected from birds at Copenhagen zoo (Cop) and Götala research station (Got) and were incubated and hatched together. Twenty-eight birds (16 Got and 12 Cop) were reared together and tested in eight different behavioural tests, measuring different aspects of fear-related behaviours as well as exploratory and social behaviours. The study revealed several differences in fear-related behaviours between the populations but none in exploratory or social behaviours. In general, one of the populations (Cop) showed more intense fear behaviours than the other (Got), which instead were less fearful in their behaviours. This indicates that breeding animals in captivity may lead to behavioural modifications, which can affect the outcome of reintroductions. The results further suggest that fear-related behaviours are dependent on the genetic background of the animals while social behaviours may be more influenced by the social environment. Since fear-related behaviours, such as predator avoidance and fear of humans, are essential for a life in the wild, these aspects are crucial for the breeding of animals in captivity for conservation purposes.

  • 57.
    Håkansson, Jennie
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    A longitudinal study of antipredator behaviour in four successive generations of two populations of captive red junglefowl2008Ingår i: Applied Animal Behaviour Science, ISSN 0168-1591, E-ISSN 1872-9045, Vol. 114, nr 3-4, s. 409-418Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Conservation breeding and reintroduction into the wild can only be an effective management tool if behaviours essential for a life in the wild are maintained in captivity. The aim of this study was to investigate how a protected captive environment influences antipredator behaviour over generations. The red junglefowl (Gallus gallus) was used as a case study. Birds from two different captive populations were followed over four generations. In the last three generations, all birds were hatched and reared in the same indoor settings. Antipredator behaviour was measured in each generation in a standardised test where the birds were exposed to a simulated predator attack. The test was divided into three parts: pre-exposure period, exposure and post-exposure periods. There was an interaction effect between Population and generation (F-3.129 = 4.84, P < 0.01) on behaviour during the pre-exposure period, suggesting that the birds "baseline" agitation level may have been altered differently in the two populations. Population differences were also found during the post-exposure period but the populations tended to become more similar over successive generations in their behaviour after the exposure. Furthermore, there were significant effects of generation (H (d.f. = 1, N = 137) = 10.94, P < 0.05) as well as population (H (d.f. = 1, N = 137) = 5.17, P < 0.05) on the immediate reaction to the simulated predator attack. In conclusion, over four successive generations, the two populations altered their antipredator behaviour and tended to become more similar. This study shows that antipredator behaviour may change over generations in a captive environment. This is likely to be one of the most crucial factors for successful reintroduction into the wild and hence, it is a very important aspect to consider for conservation breeding.

  • 58.
    Håkansson, Jennie
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Behavioural and morphological variation between captive populations of red junglefowl (Gallus gallus) - possible implications for conservation2005Ingår i: Biological Conservation, ISSN 0006-3207, Vol. 122, nr 3, s. 431-439Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The escalating threats to ecosystems worldwide have lead to a need for efficient methods to breed animals in captivity and to prepare captive-born animals for release back to the wild. However, life in captivity may lead to modifications in the animal’s behaviour mainly by genetic changes, including behavioural adaptations such as reduced predator responses. Such modifications may seriously affect survival after a reintroduction. The present study was a first screening of behavioural and morphological variation between different captive populations in standardized test situations using red junglefowl as a model species. The birds were tested in three different test situations in order to measure anti-predatory behaviour, social behaviour and exploratory behaviour. The results of this study clearly show that there are behavioural differences between the captive populations which potentially can be crucial for the animals in a reintroduction situation. However, the extent to which these differences are due to genetic changes caused by small breeding populations or adaptations to the different captive environments is not yet known, although morphological differences found suggest that genetic variation may cause some of the behavioural differences as well. The differences found imply that life in captivity can affect an animal’s behaviour and even though the red junglefowl is merely used as a model here, this suggests that these aspects may be important to consider also in other species where reintroduction is a more central motive for keeping the animals in captivity.

  • 59.
    Håkansson, Jennie
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Kerje, Susanne
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Hailer, Frank
    Andersson, Leif
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Genetic diversity and its correlation with behavioural variance in captive populations of red junglefowl - possible implications for conservation2010Manuskript (preprint) (Övrigt vetenskapligt)
  • 60.
    Jacobsen, Troels B.
    et al.
    Center for Sound Communication, Institute of Biology University of Southern Denmark.
    Mayntz, Michael
    Research and Education Kolmårdens Djurpark.
    Amundin, Mats
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Splitting Suckling Data of Bottlenose Dolphin (Tursiops truncatus) Neonates in Human Care Into Suckling Bouts2003Ingår i: Zoo Biology, ISSN 0733-3188, E-ISSN 1098-2361, Vol. 22, s. 477-488Artikel i tidskrift (Refereegranskat)
  • 61.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Behavior Genetics and the Domestication of Animals2014Ingår i: Annual Review of Animal Biosciences, ISSN 2165-8102, E-ISSN 2165-8110, Vol. 2, s. 85-104Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Across species, a similar suite of traits tends to develop in response todomestication, including modifications in behavior. Reduced fearand increased stress tolerance were central in early domestication,and many domestication-related behaviors may have developed astraits correlated to reduced fear.Genetic mechanisms involved in domesticationof behavior can be investigated by using top-down orbottom-up approaches, either starting from the behavior variationand searching for underlying genes or finding selected loci and thenattempting to identify the associated phenotypes. Combinations ofthese approaches have proven powerful, and examples of resultsfrom such studies are presented and discussed. This includes loci associatedwith tameness in foxes and dogs, as well as loci correlatedwith reduced aggression and increased sociality in chickens. Finally,some examples are provided on epigenetic mechanisms in behavior,and it is suggested that selection of favorable epigenetic variantsmayhave been an important mechanism in domestication.

  • 62.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Domestication, selection, behaviour and welfare of animals - genetic mechanisms for rapid responses2010Ingår i: Animal Welfare, ISSN 0962-7286, Vol. 19, nr S1, s. 7-9Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Increased production has been the major goal of animal breeding for many decades, and the correlated side-effects have grown tobecome a major issue in animal welfare. In this paper, the main genetic mechanisms in which such side-effects may occur arereviewed with examples from our own research in chickens. Pleiotropy, linkage and regulatory pathways are the most importantmeans by which a number of traits may be affected simultaneously by the same selection pressure. Pleiotropy can be exemplified bythe gene PMEL17 which causes a lack of black pigmentation in chickens and, simultaneously, predisposes them to become the victimsof feather pecking. Linkage is a probable reason why a limited region on chicken chromosome 1 affects many different traits, suchas growth, reproduction and fear-related behaviour. Gene regulation is affected by stress, and may cause modifications in behaviourand phenotype which are transferred from parents to offspring by means of epigenetic modifications. Insights into phenomena, suchas these, may increase our understanding not only of how artificial selection works, but also evolution at large.

  • 63.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Domestication-From behaviour to genes and back again2006Ingår i: Applied Animal Behaviour Science, ISSN 0168-1591, E-ISSN 1872-9045, Vol. 97, nr 1, s. 3-15Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    During domestication, animals have adapted with respect to behaviour and an array of other traits. This tends to give rise to a specific domestication phenotype, involving similar changes in colour, size, physiology and behaviour among different species. Hence, domestication offers a model for understanding the genetic mechanisms involved in the trade-off between behaviour and other traits in response to selection. We compared the behaviour and other phenotypic traits of junglefowl and white leghorn layers, selected for egg production (and indirectly for growth). To examine the genetic mechanisms underlying the domestication-related differences, we carried out a genome scan for quantitative trait loci (QTLs) affecting behaviour and production traits in F2-birds of a junglefowl×white leghorn intercross. Several significant or suggestive QTLs for different production traits were located and some of these coincided with QTLs for behaviour, suggesting that QTLs with pleiotropic effects (or closely linked QTLs) may be important for the development of domestication phenotypes. Two genes and their causative mutations for plumage colouration have been identified, and one of these has a strong effect on the risk of being a victim of feather pecking, a detrimental behaviour disorder. It is likely that fast and large evolutionary changes in many traits simultaneously may be caused by mutations in regulatory genes, causing differences in gene expression orchestration. Modern genomics paired with analysis of behaviour may offer a route for understanding the relation between behaviour and production and predicting possible side-effects of breeding programs.

  • 64.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi.
    Genomics: The chicken genome sequence2005Övrigt (Övrigt vetenskapligt)
    Abstract [en]

    [No abstract available]

  • 65.
    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.

  • 66.
    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.

  • 67.
    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.

  • 68.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Transgenerational epigenetic effects on animal behaviour2013Ingår i: Progress in Biophysics and Molecular Biology, ISSN 0079-6107, E-ISSN 1873-1732, Vol. 113, nr 3, s. 447-454Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Over the last decade a shift in paradigm has occurred with respect to the interaction between environmentand genes. It is now clear that animal genomes are regulated to a large extent as a result of inputfrom environmental events and experiences, which cause short- and long-term modifications in epigeneticmarkings of DNA and histones. In this review, the evidence that such epigenetic modificationscan affect the behaviour of animals is explored, and whether such acquired behaviour alterations cantransfer across generation borders. First, the mechanisms by which experiences cause epigenetic modificationsare examined. This includes, for example, methylation of cytosine in CpG positions and acetylationof histones, and studies showing that this can be modified by early experiences. Secondly, theevidence that specific modifications in the epigenome can be the cause of behaviour variation isreviewed. Thirdly, the extent to which this phenotypically active epigenetic variants can be inheritedeither through the germline or through reoccurring environmental conditions is examined. A particularlyinteresting observation is that epigenetic modifications are often linked to stress, and may possibly bemediated by steroid effects. Finally, the idea that transgenerationally stable epigenetic variants may serveas substrates for natural selection is explored, and it is speculated that they may even predispose fordirected, non-random mutations.

  • 69.
    Jensen, Per
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Andersson, Leif
    Animal genetics Swedish University of Agricultural Sciences.
    Genomics Meets Ethology: A New Route to Understanding Domestication, Behavior, and Sustainability in Animal Breeding2005Ingår i: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 34, s. 320-324Artikel i tidskrift (Refereegranskat)
  • 70.
    Jensen, Per
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Buitenhuis, B.
    Kjaer, J.
    Zanella, A.
    Mormède, P.
    Pizzari, Tom
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Genetics and genomics of animal behaviour and welfare-Challenges and possibilities2008Ingår i: Applied Animal Behaviour Science, ISSN 0168-1591, E-ISSN 1872-9045, Vol. 113, nr 4, s. 383-403Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Traditionally, the contribution of applied ethology to animal welfare science has concentrated on understanding the reactions of animals to their housing conditions. Domestication has had small effects on fundamental aspects of animal behaviour, and therefore, the needs of present day domesticated animals are closely related to the evolutionary history of the ancestors. However, the last decades have seen an unprecedented intensification of selection for increased production, which has significant side-effects on behaviour and welfare. Understanding the nature of such side-effects have therefore emerged as a central problem to animal welfare science. Modern genetics and genomics offer tools for such research, and this review outlines some of the available methods and how these have been, and could be, used to enrich animal welfare science. An outline is given on traditional genetic selection methods applied on behaviour and welfare related variables. Significant improvements in levels of fearfulness and abnormal behaviour have been achieved by selecting populations against these traits. As a next step, it is necessary to map the loci involved in affecting these traits, and quantitative trait locus (QTL) analysis have been used for this. An overview of QTL-analyses of welfare related traits in different species is given, including how this analysis has provided new insights into the genetic architecture of the stress response. Beyond allelic differences, which can be mapped with QTL-analysis, welfare related biological responses may be mediated by acquired modifications in expression levels of genes and gene complexes. This can be analysed with cDNA microarray technology, and a review of relevant work in this respect is given. Many of the changes in genetic control mechanisms observed during selection are results of evolutionary responses, for example related to sexual selection. An overview with a genetic perspective is provided of this often neglected aspect of domestication in relation to animal welfare problems. It is concluded that modern selection of farm animals pose a serious challenge to animal welfare, but also previously unknown possibilities to improve welfare by using high precision breeding techniques. © 2008 Elsevier B.V. All rights reserved.

  • 71.
    Jensen, Per
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Keeling, L.,
    Department of Animal Environment and Health Swedish University of Agricultural Science.
    Schütz, K.,
    AgResearch, Animal Behaviour and Welfare, New Zealand.
    Andersson, L.,
    Department of Medical Biochemistry and Microbiology Uppsala university.
    Morméde, P.,
    Neuroge´ne´tique et Stress Institut Francois Magendie, France.
    Brändström, H.,
    Department of Medical Sciences Uppsala university.
    Forkman, B.,
    Department of Animal Science and Animal Health Royal Veterinary and Agricultural University, Denmark.
    Kerje, S.,
    dDepartment of Medical Biochemistry and Microbiology Uppsala university.
    Fredriksson, R.,
    dDepartment of Medical Biochemistry and Microbiology Uppsala university.
    Ohlsson, C.,
    Division of Endocrinology, Department of Internal Medicine Sahlgrenska University Hospital, Göteborg.
    Mallmin, H.,
    Department of Surgical Sciences, Section of Orthopedics University Hospital, Uppsala.
    Kindmark, A.,
    Department of Medical Sciences Uppsala university.
    Feather pecking in chickens is genetically related to behavioural and developmental traits2005Ingår i: Physiology and Behavior, ISSN 0031-9384, E-ISSN 1873-507X, Vol. 86, s. 52-60Artikel i tidskrift (Refereegranskat)
  • 72.
    Jildmalm, Ronald
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Amundin, Mats
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Laska, Matthias
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Food Preferences and Nutrient Composition in Captive White-handed Gibbons, Hylobates lar2008Ingår i: International journal of primatology, ISSN 0164-0291, E-ISSN 1573-8604, Vol. 29, nr 6, s. 1535-1547Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We aimed to assess spontaneous food preferences in captive white-handed gibbons and to analyze whether they correlate with nutrient composition. Via a 2-alternative choice test, we repeatedly presented 3 male Hylobates lar with all possible binary combinations of 10 types of food that are part of their diet in captivity and found the following rank order of preference: grape > banana = fig > apple > pear > honeydew melon > carrot > tomato > cucumber > avocado. Correlational analyses revealed a highly significant positive correlation between the food preference ranking and the total carbohydrate, fructose, and glucose contents of the foods (p < 0.01, respectively). With the exception of the trace mineral selenium (p < 0.05), there was no other significant correlation with any other macro- or micronutrient. In addition, the food preferences were stable across the day because rankings obtained from tests performed at 0900, 1200, and 1500 h, respectively, did not differ significantly (p > 0.05). Our results suggest that captive white-handed gibbons are not opportunistic, but selective feeders with regard to maximizing net gain of energy because only the content of carbohydrates, but not the contents of total energy, proteins, or lipids significantly correlate with the displayed food preferences. Further, the results suggest that captive Hylobates lar, in contrast to their free-ranging conspecifics, do not display marked changes in their food selection across the day.

  • 73.
    Johansson, Nathalie
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi.
    Teat position and personality in piglets, Sus scrofa2011Självständigt arbete på grundnivå (kandidatexamen), 10,5 poäng / 16 hpStudentuppsats (Examensarbete)
    Abstract [en]

    In order to investigate if difference in personality is depended on the teat positions in piglets, Sus scrofa, 63 piglets, from 21 litters, were studied. The piglets were at an age between 9 and 31 days. 3 piglets in each of the 21 litters, one that suckled at an anterior teat, one at a middle teat, and one at a posterior teat, were studied during lactation, undisturbed activity, and introduction to a novel object respectively to new straw. In total thirteen behaviors were recorded. The only significant difference between the teat position were disputes during suckling (P=0.018). There was a tendency of playing during undisturbed activity (P=0.062) between the teat positions. There were significant differences between the litters for every behavior except for inactive piglet lying alone (P=0.108) and when exploring new straw (P=0.584). There is only evidence for behavioral differences for the frequency of disputes during suckling between piglets at different teat positions. A principal component analysis, which accounted for 64.2 % of the variance, suggested four personality traits: exploration (19.2 %), playfulness (17.5 %), interest in food (14.8 %), and interest in straw (10.9 %). However, no significant differences were found for these components for the different teat positions.

  • 74.
    Johnsson, Martin
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi.
    DNA methylation analysis of promoters in chicken brain by means of high resolution melting2010Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Domesticated and non­domesticated chickens differ in a range of morphological and behavioural traits, including differences in brain gene expression. DNA methylation of CpG dinucleotides in promoters is an important mechanism of epigenetic gene regulation. Previously, gene expression microarrays have been used to find differentially expressed genes in the brain of red junglefowl (RJF) and White Leghorn (WL) chickens. To investigate whether differential promoter DNA methylation can explain some of these expression differences, methylation sensitive high resolution melting (MS­-HRM) was used on five candidate genes taken from the expression data. Candidate genes were screened with bioinformatic software to find CpG islands overlapping predicted promoters. DNA was isolated from frozen optic tecta from a subset of the expression study birds. Bisulfite converted DNA was amplified with real­time PCR, melted, and compared to mixtures of methylated and non­methylated DNA. CpG islands adjacent to the differentially expressed transcript JMJD1C and an unannotated transcript on chromosome three were unmethylated, while a CpG island adjacent to TMEM208 was completely methylated. Additionally, CpG islands of ZMYND11 and LOC424014 appears to be at least 50% methylated, but these results are more insecure. Part of the β­-globin insulator, previously known to be methylated in non­expressing tissues, was completely methylated. The results indicate that this MS­-HRM method is suitable for methylation analysis in this material. No differential methylation between WL and RJF was found. For the unannotated transcript, JMJD1C and TMEM208, differential methylation as an explanation of differential expression in optic tecta can be excluded.

  • 75.
    Johnsson, Martin
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska högskolan.
    Gustafsson, Ida
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biologi. Linköpings universitet, Tekniska högskolan.
    Rubin, Carl-Johan
    Department of Medical Biochemistry and Michrobiology, BMC, Uppsala University, Uppsala, Sweden.
    Sahlqvist, Anna-Stina
    Department of Medical Sciences, Uppsala University, Uppsalam, Sweden.
    Jonnson, Kenneth B.
    Department of Surgical Sciences, Orthopeadics, Akademiska sjukhuset, Uppsala university, Uppsala, Sweden.
    Kjere, Susanne
    Department of Medical Sciences, Uppsala University,.
    Ekwall, Olov
    Departmet of Rheumatology and Inflammation Research, Institute of Medicine, The Sahlgrenska Academy, Gothenburg, Sweden.
    Kämpe, Olle
    Department of Medical Sciences, Uppsala University, Uppsalam, Sweden.
    Andersson, Leif
    Department of Medical Biochemistry and Michrobiology, BMC, Uppsala University, Uppsala, Sweden.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Wright, Dominic
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    A Sexual Ornament in Chickens Is Affected bu Pleiotropic Alleles at HAO1 and BMP2, Selected during Domestication2012Ingår i: PLOS Genetics, ISSN 1553-7390, Vol. 8, nr 8, s. e10002914-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Domestication is one of the strongest forms of short-term, directional selection. Although selection is typically only exerted on one or a few target traits, domestication can lead to numerous changes in many seemingly unrelated phenotypes. It is unknown whether such correlated responses are due to pleiotropy or linkage between separate genetic architectures. Using three separate intercrosses between wild and domestic chickens, a locus affecting comb mass (a sexual ornament in the chicken) and several fitness traits (primarily medullary bone allocation and fecundity) was identified. This locus contains two tightly-linked genes, BMP2 and HAO1, which together produce the range of pleiotropic effects seen. This study demonstrates the importance of pleiotropy (or extremely close linkage) in domestication. The nature of this pleiotropy also provides insights into how this sexual ornament could be maintained in wild populations.

  • 76.
    Jöngren, Markus
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Westander, Jennie
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Nätt, Daniel
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Brain gene expression in relation to fearfulness in female red junglefowl (Gallus gallus)2010Ingår i: Genes, Brain and Behavior, ISSN 1601-1848, E-ISSN 1601-183X, Vol. 9, nr 7, s. 751-758Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The biology of fear is central to animal welfare and hasbeen a major target for selection during domestication.Fear responses were studied in female red junglefowl(RJF), the ancestor of domesticated chickens. A totalof 31 females were tested in a ground predator test,an aerial predator test and a tonic immobility (TI)test, in order to assess their level of fearfulnessacross different situations. Two to six variables fromeach test were entered into a principal component(PC) analysis, which showed one major fearfulnesscomponent (explaining 27% of the variance). Based onthe PC scores, four high- and four low-fearful birds werethen selected for gene expression analysis. From eachof these birds, the midbrain region (including thalamus,hypothalamus, pituitary, mesencephalon, pons, nucleustractus solitarii and medulla oblongata), was collectedand global gene expression compared between groupsusing a 14k chicken cDNA microarray. There were 13significantly differentially expressed (DE) genes (basedonM > 1 andB > 0; FDR-adjusted P < 0.05) between thefearful and non-fearful females. Among the DE genes,we identified the neuroprotein Axin1, two potentialDNA/RNA regulating proteins and a retrotransposontranscript situated in a well-studied quantitative traitloci (QTL) region on chromosome 1, known to affectseveral domestication-related traits. The differentiallyexpressed genes may be part of a possible molecularmechanism controlling fear responses in fowl.

  • 77.
    Karlsson, Anna-Carin
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Elgland, Mathias
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Organisk Kemi. Linköpings universitet, Tekniska högskolan.
    Laur, Katriann
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Organisk Kemi. Linköpings universitet, Tekniska högskolan.
    Fyrner, Timmy
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Kemi. Linköpings universitet, Tekniska fakulteten.
    Konradsson, Peter
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Organisk Kemi. Linköpings universitet, Tekniska högskolan.
    Laska, Matthias
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Red junglefowl have individual body odors2010Ingår i: JOURNAL OF EXPERIMENTAL BIOLOGY, ISSN 0022-0949, Vol. 213, nr 10, s. 1619-1624Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Olfaction may play an important role in regulating bird behavior, and has been suggested to be involved in feather-pecking. We investigated possible differences in the body odors of red junglefowl females by using an automated olfactometer which assessed the ability of trained mice to discriminate between the odors of uropygial gland secretions (the main carrier of potential individual odors in chickens) of six feather-pecked and six non-pecked birds. All mice were clearly able to discriminate between all individual red junglefowl odors, showing that each bird has an individual body odor. We analyzed whether it was more difficult to discriminate between the odors of two feather-pecked, or two non-pecked birds, than it was to discriminate between the odors of two randomly selected birds. This was not the case, suggesting that feather-pecked birds did not share a common odor signature. Analyses using gas chromatography and mass spectrometry showed that the composition of aliphatic carboxylic acids in uropygial gland secretions differed consistently between individuals. However, chemical composition did not vary according to feather-pecking status. We conclude that red junglefowl have individual body odors which appear to be largely based on differences in the relative abundance of aliphatic carboxylic acids, but there is no evidence of systematic differences between the body odors of pecked and non-pecked birds.

  • 78.
    Karlsson, Anna-Carin
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Kerje, S
    Uppsala University.
    Andersson, L
    Uppsala University.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Genotype at the PMEL17 locus affects social and explorative behaviour in chickens2010Ingår i: BRITISH POULTRY SCIENCE, ISSN 0007-1668, Vol. 51, nr 2, s. 170-177Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    1. We studied behaviour and brain gene expression in homozygous PMEL17 genotypes, using chickens originating from an advanced White Leghorn x red junglefowl intercross. The behavioural studies consisted of three social and one explorative behaviour test. There were significant differences between the genotypes in both social and explorative behaviour. 2. Gene expression studies showed no PMEL17 expression in brain, so the genotype differences must depend on extra-neural gene expression or expression during embryonic development. However, linkage or spurious family effects (genetic drift) can not be excluded. 3. The study strongly suggests a correlated effect between plumage colour and behaviour, and we conclude that PMEL17 may have a pleiotropic effect on social and explorative behaviour in chickens.

  • 79.
    Karlsson, Anna-Carin
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Kerje, Susanne
    Uppsala University.
    Hallböök, Finn
    Uppsala University.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    The Dominant white mutation in the PMEL17 gene does not cause visual impairment in chickens.2009Ingår i: Veterinary ophthalmology, ISSN 1463-5224, Vol. 12, nr 5, s. 292-298Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Objective: To examine whether the Dominant white mutation (causing a hypopigmented phenotype in chicken) affects the visual ability and gives rise to ocular abnormalities in chickens (Gallus gallus). PROCEDURE: Chickens homozygous for either the Dominant white mutation or the wild-type alleles were tested in a visual contrast behavioral test and subjected to histological and ophthalmologic examination. RESULTS: There were no differences between the genotypes in the visual contrast behavioral test, and there were no abnormal structures among the Dominant white chickens in the ophthalmic examination. The histological sections from the Dominant white chickens did not differ from the wild-type chicken in structure, photoreceptor density, or RPE pigmentation. CONCLUSIONS: The results indicate that the Dominant white mutation in PMEL17 does not seem to affect the visual ability or eye structures in chickens.

  • 80.
    Karlsson, Anna-Carin
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Mormede, Pierre
    University Bordeaux 2.
    Kerje, Susanne
    Uppsala University.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Genotype on the Pigmentation Regulating PMEL17 Gene Affects Behavior in Chickens Raised Without Physical Contact with Conspecifics2011Ingår i: BEHAVIOR GENETICS, ISSN 0001-8244, Vol. 41, nr 2, s. 312-322Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Chickens homozygous for the Dominant white or wild-type allele of PMEL17 were subjected to a broad phenotyping in order to detect consistent differences between genotypes. To exclude feather pecking, the chickens were individually housed without physical contact, from the day of hatching, and tested for social, aggressive, fear and exploratory behaviors, and corticosterone and testosterone levels were assessed. In a principal component analysis, 53.2% of the behavior variation was explained by two factors. Factor one was an activity and social factor, and there was a significant effect of genotype on the factor scores. On factor two, related to aggressive behavior, there were significant effects of genotype, sex and their interaction. There were no genotype effects on hormone levels or any other measured non-behavioral phenotypes. Hence, differences in behavior between PMEL17 genotypes remained when negative social experiences were excluded, indicating a direct pleiotropic effect of the gene on behavior.

  • 81.
    Keeling, L.
    et al.
    Dept. of Anim. Environ. and Health, Swed. Univ. of Agricultural Sciences, PO Box 234, 53223 Skara, Sweden.
    Andersson, L.
    Dept. Med. Biochem. and Microbiol., Uppsala University, Box 597, 75124 Uppsala, Sweden, Dept. of Anim. Breeding and Genetics, Swed. Univ. of Agricultural Sciences, 75124 Uppsala, Sweden.
    Schutz, K.E.
    Schütz, K.E., Dept. of Anim. Environ. and Health, Swed. Univ. of Agricultural Sciences, PO Box 234, 53223 Skara, Sweden, AgResearch, Animal Behaviour and Welfare, Private Bag 3123, Hamilton, New Zealand.
    Kerje, Susanne
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi.
    Fredriksson, R.
    Dept. of Anim. Breeding and Genetics, Swed. Univ. of Agricultural Sciences, 75124 Uppsala, Sweden.
    Carlborg, O.
    Carlborg, Ö., Dept. of Anim. Breeding and Genetics, Swed. Univ. of Agricultural Sciences, 75124 Uppsala, Sweden, Roslin Institute, Roslin, Midlothian EH25 9PS, United Kingdom.
    Cornwallis, C.K.
    Dept. of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, United Kingdom.
    Pizzari, Tom
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi.
    Feather pecking and victim pigmentation2004Ingår i: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 431, nr 7009, s. 645-646Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    [No abstract available]

  • 82.
    Kerje, S.
    et al.
    Dept. of Anim. Breeding and Genetics, Swed. Univ. of Agricultural Sciences, BMC, Uppsala, Sweden.
    Carlborg, O.
    Carlborg, Ö., Dept. of Anim. Breeding and Genetics, Swed. Univ. of Agricultural Sciences, BMC, Uppsala, Sweden.
    Jacobsson, L.
    Dept. of Anim. Breeding and Genetics, Swed. Univ. of Agricultural Sciences, BMC, Uppsala, Sweden.
    Schutz, K.
    Schütz, K., Dept. of Anim. Environ. and Health, Section of Ethology, Swed. Univ. of Agricultural Sciences, Skara, Sweden.
    Hartmann, C.
    Dept. of Anim. Breeding and Genetics, Swed. Univ. of Agricultural Sciences, BMC, Uppsala, Sweden.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi.
    Andersson, L.
    Dept. of Anim. Breeding and Genetics, Swed. Univ. of Agricultural Sciences, BMC, Uppsala, Sweden, Dept. of Med. Biochem./Microbiology, Uppsala University, BMC, Uppsala, Sweden, Dept. of Med. Biochem./Microbiology, Uppsala University, Box 597, S-751 24 Uppsala, Sweden.
    The twofold difference in adult size between the red junglefowl and White Leghorn chickens is largely explained by a limited number of QTLs2003Ingår i: Animal Genetics, ISSN 0268-9146, E-ISSN 1365-2052, Vol. 34, nr 4, s. 264-274Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A large intercross between the domestic White Leghorn chicken and the wild ancestor, the red junglefowl, has been used in a Quantitative Trait Loci (QTL) study of growth and egg production. The linkage map based on 105 marker loci was in good agreement with the chicken consensus map. The growth of the 851 F2 individuals was lower than both parental lines prior to 46 days of age and intermediate to the two parental lines thereafter. The QTL analysis of growth traits revealed 13 loci that showed genome-wide significance. The four major growth QTLs explained 50 and 80% of the difference in adult body weight between the founder populations for females and males, respectively. A major QTL for growth, located on chromosome 1 appears to have pleiotropic effects on feed consumption, egg production and behaviour. There was a strong positive correlation between adult body weight and average egg weight. However, three QTLs affecting average egg weight but not body weight were identified. An interesting observation was that the estimated effects for the four major growth QTLs all indicated a codominant inheritance.

  • 83.
    Kerje, S.
    et al.
    Dept. of Anim. Breeding and Genetics, Swed. Univ. of Agricultural Sciences, Uppsala, Sweden.
    Lind, J.
    Dept. of Anim. Breeding and Genetics, Swed. Univ. of Agricultural Sciences, Uppsala, Sweden.
    Schutz, K.
    Schütz, K., Dept. of Anim. Environ. and Health, Section of Ethology, Swed. Univ. of Agricultural Sciences, Skara, Sweden.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi.
    Andersson, L.
    Dept. of Anim. Breeding and Genetics, Swed. Univ. of Agricultural Sciences, Uppsala, Sweden, Dept. of Med. Biochem./Microbiology, Uppsala University, Uppsala, Sweden, Dept. of Med. Biochem./Microbiology, Uppsala University, Box 597, SE-751 24 Uppsala, Sweden.
    Melanocortin 1-receptor (MC1R) mutations are associated with plumage colour in chicken2003Ingår i: Animal Genetics, ISSN 0268-9146, E-ISSN 1365-2052, Vol. 34, nr 4, s. 241-248Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The co-segregation of plumage colour and sequence polymorphism in the melanocortin 1-receptor gene (MC1R) was investigated using an intercross between the red junglefowl and White Leghorn chickens. The results provided compelling evidence that the Extended black (E) locus controlling plumage colour is equivalent to MC1R. E/MC1R was assigned to chromosome 11 with overwhelming statistical support. Sequence analysis indicated that the E92K substitution, causing a constitutively active receptor in the sombre mouse, is the most likely causative mutation for the Extended black allele carried by the White Leghorn founders in this intercross. The MC1R sequence associated with the recessive buttercup (ebc) allele indicated that this allele evolved from a dominant Extended black allele as it shared the E92K and M71T substitutions with some E alleles. It also carried a third missense mutation H215P which thus may interfere with the constitutive activation of the receptor caused by E92K (and possibly M71T).

  • 84.
    Kerje, S.
    et al.
    Dept. Med. Biochem. and Microbiol., Uppsala University, SE-751 24 Uppsala, Sweden.
    Sharma, P.
    Department of Poultry Science, University of Arkansas, Fayetteville, AR 72701, United States.
    Gunnarsson, U.
    Dept. Med. Biochem. and Microbiol., Uppsala University, SE-751 24 Uppsala, Sweden.
    Kim, H.
    Dept. of Biochemistry and Biophysics, Stockholm University, SE-106 91 Stockholm, Sweden.
    Bagchi, S.
    Dept. of Anim. Breeding and Genetics, Swed. Univ. of Agricultural Sciences, SE-751 24 Uppsala, Sweden.
    Fredriksson, R.
    Department of Neuroscience, Uppsala University, SE-751 24 Uppsala, Sweden.
    Schutz, K.
    Schütz, K., Dept. of Anim. Environ. and Health, Section of Ethology, Swed. Univ. of Agricultural Sciences, SE-532 23 Skara, Sweden.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi.
    Von, Heijne G.
    Von Heijne, G., Dept. of Biochemistry and Biophysics, Stockholm University, SE-106 91 Stockholm, Sweden.
    Okimoto, R.
    Department of Poultry Science, University of Arkansas, Fayetteville, AR 72701, United States.
    Andersson, L.
    Dept. Med. Biochem. and Microbiol., Uppsala University, SE-751 24 Uppsala, Sweden, Dept. of Anim. Breeding and Genetics, Swed. Univ. of Agricultural Sciences, SE-751 24 Uppsala, Sweden, Dept. Med. Biochem. and Microbiol., Uppsala University, BMC, SE-751 24 Uppsala, Sweden.
    The Dominant white, Dun and Smoky color variants in chicken are associated with insertion/deletion polymorphisms in the PMEL17 gene2004Ingår i: Genetics, ISSN 0016-6731, E-ISSN 1943-2631, Vol. 168, nr 3, s. 1507-1518Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Dominant white, Dun, and Smoky are alleles at the Dominant white locus, which is one of the major loci affecting plumage color in the domestic chicken. Both Dominant white and Dun inhibit the expression of black eumelanin. Smoky arose in a White Leghorn homozygous for Dominant white and partially restores pigmentation. PMEL17 encodes a melanocyte-specific protein and was identified as a positional candidate gene due to its role in the development of eumelanosomes. Linkage analysis of PMEL17 and Dominant while using a red jungle fowl/White Leghorn intercross revealed no recombination between these loci. Sequence analysis showed that the Dominant white allele was exclusively associated with a 9-bp insertion in exon 10, leading to an insertion of three amino acids in the PMEL17 transmembrane region. Similarly, a deletion of five amino acids in the transmembrane region occurs in the protein encoded by Dun. The Smoky allele shared the 9-bp insertion in exon 10 with Dominant white, as expected from its origin, but also had a deletion of 12 nucleotides in exon 6, eliminating four amino acids from the mature protein. These mutations are, together with the recessive silver mutation in the mouse, the only PMEL17 mutations with phenotypic effects that have been described so far in any species.

  • 85.
    Kirkden, Richard
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Lindqvist, Christina
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi.
    Jensen, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Effects of domestication on filial motivation and imprinting in chicks: comparison of red junglefowl and White Leghorns2008Ingår i: Animal Behaviour, ISSN 0003-3472, E-ISSN 1095-8282, Vol. 76, nr 2, s. 287-295Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Domestication has been reported to reduce learning ability and to alter social behaviour. We compared the development of filial behaviour of domestic chickens, Gallus gallus domesticus, and the ancestral red junglefowl, Gallus gallus. We investigated the tendency of naïve chicks to approach conspicuous stimuli, as a measure of filial motivation, and the development of a preference for familiar stimuli over unfamiliar ones, as a measure of imprinting and hence of social-learning ability. Chicks were placed in an arena containing two stimuli (a red cylinder and a blue ball) after being housed individually with one of these stimuli for 0, 6, 12, 24, 36, 48 or 60 h. During a 20 min trial, observations were made of their latency to approach each stimulus and the amount of time spent close to them. With no prior exposure to either stimulus (0 h), the breeds did not differ in their readiness to approach stimuli, suggesting no difference in filial motivation. However, the breeds differed in their initial preferences between the two stimuli tested and in their ability to imprint on them. Junglefowl chicks showed an initial preference for the red cylinder, but imprinted equally well on both stimuli, whereas Leghorn chicks showed no initial preference but imprinted relatively poorly on the red cylinder. We suggest that junglefowl chicks may be more flexible in their ability to imprint on stimuli than domestic chicks, however, a greater variety of stimulus types must be tested to confirm this. © 2008 The Association for the Study of Animal Behaviour.

  • 86.
    Kjeldmand, Luna
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Hernandez Salazar, Laura Teresa
    Instituto de Neuro-Etologia, Universidad Veracruzana.
    Laska, Matthias
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Olfactory sensitivity for sperm-attractant aromatic aldehydes: a comparative study in human subjects and spider monkeys2011Ingår i: Journal of Comparative Physiology A, ISSN 0340-7594, Vol. 197, s. 15-23Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Using a three-alternative forced-choice ascendingstaircase procedure, we determined olfactory detectionthresholds in 20 human subjects for seven aromatic aldehydesand compared them to those of four spider monkeystested in parallel using an operant conditioning paradigm.With all seven odorants, both species detected concentrations\1 ppm, and with several odorants single individualsof both species even discriminated concentrations\1 ppbfrom the solvent. No generalizable species differences inolfactory sensitivity were found despite marked differencesin neuroanatomical and genetic features. The acrossodorantpatterns of sensitivity correlated significantlybetween humans and spider monkeys, and both specieswere more sensitive to bourgeonal than to lilial, cyclamal,canthoxal, helional, lyral, and 3-phenylpropanal. No significantcorrelation between presence/absence of an oxygen-containing moiety attached to the benzene ring orpresence/absence of an additional alkyl group next to thefunctional aldehyde group, and olfactory sensitivity wasfound in any of the species. However, the presence of atertiary butyl group in para position (relative to the functionalaldehyde group) combined with a lack of an additionalalkyl group next to the functional aldehyde groupmay be responsible for the finding that both species weremost sensitive to bourgeonal.

  • 87.
    Kylhammar, Martin
    et al.
    Linköpings universitet, Filosofiska fakulteten. Linköpings universitet, Institutionen för tema.
    Kylhammar, Martin
    Linköpings universitet, Filosofiska fakulteten. Linköpings universitet, Institutionen för tema.
    Beckman, Svante
    Linköpings universitet, Filosofiska fakulteten. Linköpings universitet, Institutionen för studier av samhällsutveckling och kultur, Tema Kultur och samhälle.
    Beckman, Svante
    Linköpings universitet, Filosofiska fakulteten. Linköpings universitet, Institutionen för studier av samhällsutveckling och kultur, Tema Kultur och samhälle.
    Lind, Ingemar
    Lind, Ingemar
    Nilsson, Göran B.
    Nilsson, Göran B.
    Sjölander, Sverre
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi.
    Sjölander, Sverre
    Linköpings universitet, Tekniska högskolan. Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi.
    Torekull, Bertil
    Torekull, Bertil
    Widstrand, Carl
    Widstrand, Carl
    Vad är det för vits med humor?1988Övrigt (Övrig (populärvetenskap, debatt, mm))
  • 88.
    Königson, Sara
    et al.
    Institute of Coastal Research, Swedish Board of Fisheries.
    Fjälling, Arne
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Lunneryd, Sven-Gunnar
    Institute of Coastal Research, Swedish Board of Fisheries.
    Grey seal induced catch losses in the herring gillnet fisheries in the northern Baltic2007Ingår i: NAMMCO scientific publications, ISSN 1560-2206, E-ISSN 2309-2491, Vol. 6, s. 203-213Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The interaction between grey seals (Halichoerus grypus) and the Baltic fishery for herring (Clupea harengus) was investigated for the period 2000-2004, using a three level perspective. Data from the official EU log-book system, data from a voluntary log book system, and data from field studies were combined. It was found, based on records from the official log-book and using a method with paired data compensating for temporal variations in catches and seal activity, that catches were significantly higher for fishing days when there were no seal interactions recorded during setting or lifting the nets, compared to days when there were such notations (0.59 and 1.03 kg /m net * day respectively; p< 0.001). It was found that the frequency of seal-disturbed fishing efforts, encompassing 30 % of all records of herring gillnet fishing in the official log-book, was probably an under-estimation and explained by the fact that making notes on seal interactions are optional for the fisherman. The corresponding figure of the occurrences of seal-disturbed fishing efforts was 60% in a voluntary log book system, which requires the contracted fishermen to record all occurring seal-interactions, in addition to detailed data on the whole of the fishing operation. There was a pronounced variation in the frequency of seal-disturbed fishing efforts in relation to the time of the year. The interaction was least in the early summer, and reached a maximum at the end of the year. The variation is alleged to be dependent on the life cycle of the seals and its prey, herring. It was found that the calculated seal-induced losses were larger than the occurring number of seals in the area reasonably could have consumed. It was therefore deducted that there was a significant hidden catch-reducing scaring effect from seals’ presence near the nets. The catches in the herring gillnet fishery decreased over the investigated period, whereas the catches in the trawling fishery increased, as revealed by the official log-book data. The variances in the catches were however too large to allow for an analysis of possible effects of seal interactions. The method that worked best for estimating the catch losses was using paired data which compensates for temporal variations in catches and intensity of seal interaction. A method using nets baited with marked fish for estimating the hidden losses was tested, but did not work well since seals removed more fish than the method could accept. Seals visited the experimental herring nets in 14 of the 19 trials. In 11 cases, more than 95% of the marked fish went missing. It is argued that the herring gillnet fishery in the north Baltic is severely affected by the seals-fisheries conflict.

  • 89.
    Larsson, Linda
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Laska, Matthias
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Ultra-high olfactory sensitivity for the human sperm-attractant aromaticaldehyde bourgeonal in CD-1 mice2011Ingår i: Neuroscience research, ISSN 0168-0102, E-ISSN 1872-8111, Vol. 71, nr 4, s. 355-360Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Recent studies have shown that certain aromatic aldehydes are ligands for olfactory receptors expressedin mammalian sperm cells and induce sperm chemotaxis. Using a conditioning paradigm, the olfactorysensitivity of five CD-1 mice for seven aromatic aldehydes was investigated. With all seven stimuli, themice discriminated concentrations as low as 0.01 ppm (parts per million) from the solvent, and withbourgeonal the animals even detected concentrations as low as 0.1 ppq (parts per quadrillion) whichconstitutes the lowest olfactory detection threshold value reported in this species so far. The presence ofa tertiary butyl group in para-position (relative to the functional aldehyde group) combined with a lack ofan additional alkyl group next to the functional aldehyde group may be responsible for the extraordinarysensitivity of the mice for bourgeonal.

  • 90.
    Laska, Matthias
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Olfactory Perception of 6 Amino Acids by Human Subject2010Ingår i: Chemical Senses, ISSN 0379-864X, E-ISSN 1464-3553, Vol. 35, nr 4, s. 279-287Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The olfactory properties of 6 amino acids were assessed in 20 human subjects using psychophysical tests of detectability,discriminability, and chemesthesis. Mean olfactory detection thresholds were found to be 10 lM for D-methionine, 80 lM forL-methionine, 200 lM for L-cysteine, 220 lM for D-cysteine, 75 mM for D-proline, and 100 mM for L-proline. When presentedat clearly detectable and intensity-matched concentrations, the subjects readily discriminated between the odors of the L-formsof cysteine, methionine, and proline, whereas they failed to distinguish between the L- and D-forms of a given amino acid. Thesubjects also failed in localizing the side of monorhinal stimulation with all 6 amino acids when presented at the sameconcentrations as in the discrimination tasks. These results suggest that amino acids may contribute to the flavor of food notonly as taste stimuli but also as olfactory stimuli perceived via ortho- or retronasal smelling. In contrast, it is unlikely that aminoacids contribute to flavor perception via chemesthesis. Given that the odors of 4 of the 6 amino acids tested here weredetected at concentrations lower than their corresponding taste detection thresholds, this may have important implications forthe widespread use of amino acids as food additives as well as for the evaluation of off-flavors caused by amino acids.

  • 91.
    Laska, Matthias
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    The Human Sense of Smell - Our Noses are Much Better that We Think!2011Ingår i: Senses and the City: An interdiciplinary approach to urban sensescapes / [ed] Madalina Diaconu, Eva Heuberger, Ruth Mateus-Berr, Lukas Marcel Vosicky, Wien: Lit Verlag , 2011, s. 145-153Kapitel i bok, del av antologi (Övrigt vetenskapligt)
    Abstract [en]

    The papers collected in this volume discuss the sensory dimension of cityscapes, with focus on touch and smell. Both have been traditionally considered "lower senses" and thus unworthy of being cultivated - objects of social prohibitions and targets of suppressing strategies in modern architecture and city planning. The book brings together approaches from anthropology, aesthetics, the theory of architecture, art and design research, psychophysiology, ethology, analytic chemistry, etc. (Series: Austria: Forschung und Wissenschaft - Interdisziplinar - Vol. 4)

  • 92.
    Laska, Matthias
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Joshi, Dipa
    Department of Neurobiology Yale University School of Medicine, USA.
    Shepherd, Gordon M.
    Department of Neurobiology Yale University School of Medicine, USA.
    Olfactory discrimination ability of CD-1 mice for aliphatic aldehydes as a function of stimulus concentration.2007Ingår i: Journal of Comparative Physiology A. Sensory, neural, and behavioral physiology, ISSN 0340-7594, E-ISSN 1432-1351, Vol. 193, s. 955-961Artikel i tidskrift (Refereegranskat)
  • 93.
    Laska, Matthias
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Joshi, Dipa
    Department of Neurobiology Yale University School of Medicine, New Haven, USA.
    Shepherd, Gordon M.
    Department of Neurobiology Yale University School of Medicine, New Haven, USA.
    Olfactory sensitivity for aliphatic aldehydes in CD-1 mice2006Ingår i: Behavioural Brain Research, ISSN 0166-4328, E-ISSN 1872-7549, Vol. 167, s. 349-354Artikel i tidskrift (Refereegranskat)
  • 94.
    Laska, Matthias
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Lord, Elin
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Selin, Sandra
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Amundin, Mats
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Olfactory Discrimination of Aliphatic Odorants in South African Fur Seals (Arctocephalus pusillus)2010Ingår i: JOURNAL OF COMPARATIVE PSYCHOLOGY, ISSN 0735-7036, Vol. 124, nr 2, s. 187-193Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Using a food-rewarded, two-choice, instrumental conditioning paradigm we assessed the ability of South African fur seals, Arctocephalus pusillus, to discriminate between members of five chemical classes of aliphatic odorants presumed to differ in their abundance in the marine chemical environment. We found that the fur seals were able to distinguish between 24 of the 25 odor pairs presented and thus have a well-developed ability to discriminate between structurally related odorants, that aliphatic n-acetic esters were significantly more poorly discriminated by the fur seals than aliphatic n-aldehydes and n-carboxylic acids, and a lack of correlations between discrimination performance and structural similarity of odorants in terms of differences in carbon chain length. These results suggest that the sense of smell may play an important and hitherto underestimated role in regulating the behavior of fur seals. Further, they support the notion that regular connections between the perceived quality of odorants and their molecular structural properties are not a general phenomenon but appear to be odorant class- and species-specific. Our data support the hypothesis that a species chemical environment may affect its olfactory capabilities.

  • 95.
    Laska, Matthias
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Persson, O.
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    Salazar, L.T.H.
    Universidad Veracruzana.
    Olfactory sensitivity for alkylpyrazines - A comparative study in CD-1 mice and spider monkeys2009Ingår i: Journal of Experimental Zoology Part A: Ecological Genetics and Physiology, ISSN 1932-5223, Vol. 311, nr 4, s. 278-288Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Using a conditioning paradigm, the olfactory sensitivity of four CD-1 mice for six alkylpyrazines was investigated. With all six stimuli, the animals discriminated concentrations =0.1 ppm (parts per million) from the odorless solvent, and with three of the six stimuli the animals were even able to detect concentrations =0.1 ppb (parts per billion). Four spider monkeys tested in parallel were found to detect five of the same six stimuli at concentrations less than1ppm and with one stimulus they were able to discriminate concentrations =1ppb from the solvent. The results showed CD-1 mice to be more sensitive than spider monkeys with five of the six alkylpyrazines tested. There was a significant positive correlation between sensitivity and the number of alkyl groups attached to the pyrazine (Pyr) ring in both species. A comparison of the detection thresholds obtained here to those obtained in human subjects suggests that neither the number of functional olfactory receptor genes nor the absolute or the relative size of the olfactory bulbs reliably predict a species olfactory sensitivity. These threshold data may provide useful information for the choice of adequate stimulus concentrations in electrophysiological or imaging studies of the olfactory system or investigations of the discriminative abilities of mice and spider monkeys.

  • 96.
    Laska, Matthias
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Persson Suorra, J.
    Rivas Bautista, R.M.
    Hernandez Salazar, L.T.
    Taste difference thresholds for monosodium glutamate and sodium chloride in pigtail macaques (Macaca nemestrina) and spider monkeys (Ateles geoffroyi)2008Ingår i: American Journal of Primatology, ISSN 0275-2565, E-ISSN 1098-2345, Vol. 70, nr 8, s. 839-847Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The purpose of this study was to determine taste difference thresholds for monosodium glutamate (MSG) and sodium chloride (NaCl) in pigtail macaques (Macaca nemestrina) and spider monkeys (Ateles geoffroyi). Using a two-bottle preference test of brief duration, three animals of each species were presented with four different reference concentrations of 50, 100, 200, and 400 mM of a tastant and tested for their ability to discriminate these from lower concentrations of the same tastant. The just noticeable differences (JNDs), expressed as Weber ratios (ΔI/I), were found to range from 0.1 to 0.5 for MSG and 0.2 to 0.45 for NaCl in the pigtail macaques, with a significant tendency for higher Weber ratios with higher reference concentrations. In the spider monkeys, JNDs ranged from 0.15 to 0.4 for MSG and 0.1 to 0.25 for NaCl, with Weber ratios staying fairly constant across the reference concentrations tested. Thus, the JNDs were found to be generally similar in both species and to be at least as low as those found in humans for MSG and NaCl, as well as those found in spider monkeys for sucrose. The results support the assumption that both pigtail macaques and spider monkeys may use differences in perceived intensity of MSG and NaCl as a criterion for food selection. © 2008 Wiley-Liss, Inc.

  • 97.
    Laska, Matthias
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Ringh, Anna
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    How Big is the Gap between Detection and Recognition of Aliphatic Aldehydes?2009Ingår i: Chemical Senses, ISSN 0379-864X, E-ISSN 1464-3553, Vol. 34, nr 7, s. A108-A109Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    It is widely agreed that two different measures of olfactory sensitivity can be distinguished: a detection threshold, defined as the lowest concentration at which an odorant can be detected or discriminated from a blank stimulus, and a recognition  threshold,  defined as the lowest concentration at which an odorant can be assigned a recog- nizable quality or discriminated  from another  odorant. It is further widely agreed that the detection  threshold  is lower than the recog- nition  threshold.  Surprisingly  few studies,  however, have investi- gated the magnitude of the difference in concentration between olfactory  detection  and  recognition  thresholds.  It  was therefore the aim of the present study to determine olfactory detection thresh- olds for five aliphatic  aldehydes  (C4-C8) in a group  of 16 human subjects, and to assess the ability of the same subjects to discrim- inate between the same odorants presented  at different concentra- tions above their individual detection thresholds.  We found that as a group the subjects significantly discriminated  between 4 of the 10 odorant pairs when presented  at a factor  of 100, and 7 of the 10 odorant pairs when presented at a factor of 1000 above the individ- ual detection  thresholds.  The 3 remaining  odorant pairs were not discriminated  above chance level even when presented  at a factor of 1000 above  detection  threshold.  However,  single subjects suc- cessfully discriminated  between  certain  aldehyde  pairs  presented at a factor as low as 3 above detection threshold.  Further, a signif- icant negative correlation between discrimination performance and structural similarity of the aldehydes tested was found. The results demonstrate that  the  gap  between  detection  and  recognition  of aliphatic  aldehydes  is odorant pair-dependent but  – at the grouplevel – spans at least a factor  of 100.

  • 98.
    Laska, Matthias
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Ringh, Anna
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska högskolan.
    How big is the gap between olfactory detection and recognition of aliphatic aldehydes?2010Ingår i: Attention, Perception, & Psychophysics, ISSN 1943-393X, Vol. 72, nr 3, s. 806-812Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aim of the present study was to determine the magnitude of the difference in concentration between olfactory detection and recognition thresholds of aliphatic aldehydes. To this end, we first determined olfactory detection thresholds for n-butanal, n-pentanal, n-hexanal, n-heptanal, and n-octanal in a group of 16 subjects and then assessed their ability to discriminate between all possible binary pairs of the same odorants presented at different concentrations above their individual detection thresholds. We found that the gap between detection and recognition of aliphatic aldehydes is odorant pair dependent and, at the group level, spans at least a factor of 100. However, single subjects successfully discriminated between certain aldehyde pairs presented at a factor as low as 3 above detection threshold. Our approach to determining olfactory recognition thresholds, using a performance-based measure rather than verbal labeling, not only avoids the problem of semantic ambiguity and arguable criteria, but also is applicable to nonhuman species, allowing for interspecific comparisons of recognition thresholds and of the gap between detection and recognition of odorants. The raw discrimination data from this study are available as a supplement from http://app.psychonomic-journals.org/content/supplemental.

  • 99.
    Laska, Matthias
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Rivas Bautista, Rosa Mariela
    Instituto de Neuro-Etologia.
    Hernandez Salazar, Laura Teresa
    Instituto de Neuro-Etologia.
    Gustatory Responsiveness to Six Bitter Tastants in Three Species of Nonhuman Primates2009Ingår i: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 35, s. 560-571Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Gustatory responsiveness of six adult squirrel monkeys, four spider monkeys, and five pigtail macaques to six bitter tastants was assessed in two-bottle preference tests of brief duration (2 min). Animals were given the choice between a 30-mM sucrose solution and defined concentrations of a bitter tastant dissolved in a 30-mM sucrose solution. With this procedure, Saimiri sciureus, Ateles geoffroyi, and Macaca nemestrina were found to significantly discriminate concentrations as low as 0.2, 0.05, and 0.1 mM quinine hydrochloride; 1, 1, and 0.05 mM caffeine; 20, 5, and 1 mM naringin; 5, 2, and 1 mM salicin; 0.01, 0.001, and 0.02 mM sucrose octaacetate; and 0.05, 0.01, and 0.5 mM denatonium benzoate, from the alternative stimulus. With the exception of naringin in the pigtail macaques, all three species rejected all suprathreshold concentrations of all bitter tastants tested. The spider monkeys and the pigtail macaques displayed the lowest taste avoidance thresholds with three of the six tastants each; in contrast, the squirrel monkeys displayed the highest taste avoidance thresholds with four of the six tastants. The across-tastant patterns of taste avoidance thresholds were identical in spider monkeys and squirrel monkeys; both species displayed the following order of sensitivity: sucrose octaacetate > denatonium benzoate > quinine hydrochloride > caffeine > salicin > naringin. All three primate species were more sensitive to the two artificial tastants (sucrose octaacetate and denatonium benzoate) compared to the four naturally occurring tastants. However, the concentrations detected by all three primate species with the four naturally occurring tastants are well below those reported in plants or arthropods consumed by these species suggesting that they may use bitterness as a criterion for food selection.

  • 100.
    Laska, Matthias
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Zoologi. Linköpings universitet, Tekniska högskolan.
    Rivas Bautista, Rosa Mariela
    2Instituto de Neuro-Etologia Universidad Veracruzana, Mexico.
    Höfelmann, Daniela
    Department of Medical Psychology University of Munich, Germany.
    Sterlemann, Vera
    3Department of Medical Psychology University of Munich, Germany.
    Hernandez Salazar, Laura Teresa
    2Instituto de Neuro-Etologia Universidad Veracruzana, Mexico.
    Olfactory sensitivity for putrefaction-associated thiols and indols in three species of non-human primate2007Ingår i: Journal of Experimental Biology, ISSN 0022-0949, E-ISSN 1477-9145, Vol. 210, nr 23, s. 4169-4178Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Using a conditioning paradigm, the olfactory sensitivity of four spider monkeys, three squirrel monkeys and three pigtail macaques to four thiols and two indols, substances characteristic of putrefaction processes and faecal odours, was assessed. With all odorants, the animals significantly discriminated concentrations below 1 p.p.m. (part per million) from the odourless solvent, and in several cases individual animals even demonstrated thresholds below 1 p.p.t. (part per trillion). The detection thresholds of 0.03 p.p.t. for indol in Saimiri sciureus and Macaca nemestrina and 0.96 p.p.t. for ethanethiol in Ateles geoffroyi represent the lowest values among the more than 50 odorants tested so far with these species and are in the same order of magnitude as the lowest detection thresholds reported so far in the rat and the mouse. The results showed (a) all three species of non-human primate to have a highly developed olfactory sensitivity for putrefaction-associated odorants, and (b) a significant correlation between perceptibility in terms of olfactory detection threshold and carbon chain length of the thiols, and a marked effect of the presence vs absence of a methyl group on perceptibility of the indols tested in two of the three species. The results support the hypotheses that (a) between-species differences in neuroanatomical or genetic features may not be indicative of olfactory sensitivity, and (b) within-species differences in olfactory sensitivity may reflect differences in the behavioural relevance of odorants.

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