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David W Macdonald - One of the best experts on this subject based on the ideXlab platform.

  • patterns of genital tract mustelid gammaherpesvirus 1 musghv 1 reactivation are linked to stressors in european badgers Meles Meles
    Biomolecules, 2021
    Co-Authors: Mingshan Tsai, David W Macdonald, Chris Newman, Sarah Francois, Christina D Buesching
    Abstract:

    Gammaherpesvirus reactivation can promote diseases or impair reproduction. Understanding reactivation patterns and associated risks of different stressors is therefore important. Nevertheless, outside the laboratory or captive environment, studies on the effects of stress on gammaherpesvirus reactivation in wild mammals are lacking. Here we used Mustelid gammaherpesvirus 1 (MusGHV-1) infection in European badgers (Meles Meles) as a host–pathogen wildlife model to study the effects of a variety of demographic, physiological and environmental stressors on virus shedding in the genital tract. We collected 251 genital swabs from 150 free-ranging individuals across three seasons and screened them for the presence of MusGHV-1 DNA using PCR targeting the DNA polymerase gene. We explored possible links between MusGHV-1 DNA presence and seven variables reflecting stressors, using logistic regression analysis. The results reveal different sets of risk factors between juveniles and adults, likely reflecting primary infection and reactivation. In adults, virus shedding was more likely in badgers in poorer body condition and younger than 5 years or older than 7; while in juveniles, virus shedding is more likely in females and individuals in better body condition. However, living in social groups with more cubs was a risk factor for all badgers. We discuss possible explanations for these risk factors and their links to stress in badgers.

  • A non-invasive method to assess the reproductive status of the European badger (Meles Meles) from urinary sex-steroid metabolites
    General and comparative endocrinology, 2020
    Co-Authors: Nadine Adrianna Sugianto, David W Macdonald, Chris Newman, Martin Dehnhard, Christina D Buesching
    Abstract:

    Abstract Due to their unique reproductive physiology and behaviour, European badgers (Meles Meles) are often used as a model to study mammalian reproduction. For reproductive endocrinology, circulating hormone levels are conventionally measured directly from blood samples. However, routine blood sampling is often not practical for wild animals and may induce stress affecting measurement accuracy. Non-invasive alternatives are thus of interest. Circulating hormones are metabolized through different routes, either by the kidneys, to be excreted through urine, or by the liver, to be excreted through faeces. These metabolites can thus be used as a proxy of hormone measurements, provided the species-specific metabolic characteristics are known. Here we tested the suitability of measuring urinary metabolites of circulating plasma sex-steroid hormones (testosterone in males and oestrogen in females) with enzyme immunoassays to assess the reproductive status of the European badger (Meles Meles). Biological validation evidenced that urinary testosterone metabolite (UTM) and urinary total oestrogen metabolite (UEM) excretion patterns both corresponded with seasonal badger reproductive patterns on a population level, signaling correlation over a broad time frame. On an individual level, concurrent sampling of urine and plasma showed that male plasma testosterone and UTM levels correlated significantly across seasons, but no short term correlation was evident for total oestrogen and UEM in females. Thus, in badgers, urinary sex-steroid metabolites can be used reliably in the short term to assess male reproductive status at the individual level, but only at the broader population level for females.

  • effects of mustelid gammaherpesvirus 1 musghv 1 reactivation in european badger Meles Meles genital tracts on reproductive fitness
    Pathogenetics, 2020
    Co-Authors: Mingshan Tsai, Chris Newman, David W Macdonald, Andrew W. Byrne, Ursula Fogarty, James Okeeffe, Christina D Buesching
    Abstract:

    Reactivation of latent Gammaherpesvirus in the genital tract can lead to reproductive failure in domestic animals. Nevertheless, this pathophysiology has not received formal study in wild mammals. High prevalence of Mustelid gammaherpesvirus 1 (MusGHV-1) DNA detected in the genital tracts of European badgers (Meles Meles) implies that this common pathogen may be a sexual transmitted infection. Here we used PCR to test MusGHV-1 DNA prevalence in genital swabs collected from 144 wild badgers in Ireland (71 males, 73 females) to investigate impacts on male fertility indicators (sperm abundance and testes weight) and female fecundity (current reproductive output). MusGHV-1 reactivation had a negative effect on female reproduction, but not on male fertility; however males had a higher risk of MusGHV-1 reactivation than females, especially during the late-winter mating season, and genital MusGHV-1 reactivation differed between age classes, where 3–5 year old adults had significantly lower reactivation rates than younger or older ones. Negative results in foetal tissues from MusGHV-1 positive mothers indicated that cross-placental transmission was unlikely. This study has broader implications for how wide-spread gammaherpesvirus infections could affect reproductive performance in wild Carnivora species.

  • encoded information within urine influences behavioural responses among european badgers Meles Meles
    2019
    Co-Authors: Tanesha M Allen, Chris Newman, David W Macdonald, Nadine Adrianna Sugianto, Charlotte Ryder, Christina D Buesching
    Abstract:

    Metabolic by-products like sex-steroid metabolites convey information regarding an individual’s physiological fitness and reproductive state. Urine and faeces containing these excreted metabolites can function as cues for conspecifics within social contexts, particularly for mate selection. Our pilot study investigated in scent provisioning experiments how donor- and responder-related characteristics influenced behavioural responses towards excreted sex-steroid metabolites. We used 51 urine samples with known urinary hormone concentrations (determined by EIA corrected for specific gravity) collected from known individuals in a high-density population of European badgers ( Meles Meles ) in Wytham Woods, Oxfordshire, UK during the spring mating season. Samples were provided in Eppendorf tubes pushed into the ground near badger setts to assess how response likelihood, sniff duration, and countermarking responses varied according to donor-related traits (age, sex, group familiarity and hormone concentrations). From 143 videos containing 26 identifiable adult responders, we observed adult badgers modifying their behaviour towards urine samples based on the perceived relevance to their own traits with badgers investigating and countermarking urine from opposite-sex donors more often than urine from same-sex donors. This suggests that urine-marking can serve as an adaptive signal for individual advertisement. Additionally, all badgers were more likely to investigate male urine (containing testosterone) than female urine (containing oestradiol); however, no other clear effects of sex-steroid metabolites were noticed. We consider that this could be a feature of the social evolution of badgers or arise because badgers signal reproductive status through other olfactory secretions, notably their unique subcaudal gland marking behaviour.

  • genital tract screening finds widespread infection with mustelid gammaherpesvirus 1 in the european badger Meles Meles
    Journal of Wildlife Diseases, 2018
    Co-Authors: Alice Kent, Chris Newman, David W Macdonald, Bernhard Ehlers, Tom A Mendum, Mark A Chambers, Christina D Buesching
    Abstract:

    ABSTRACT:  Sexually transmitted diseases (STDs) can be important drivers of population dynamics because of their negative effects on reproduction. However, screening for STDs, especially in wildlife populations, is widely neglected. Using the promiscuous, polygynandrous European badger (Meles Meles) as a model, we investigated the presence and prevalence of herpesviruses (HVs) in a wild, high-density population and assessed potential differences in somatic fitness and female reproductive condition between infected and uninfected individuals. We collected n=98 genital swabs from 71 females (51 adults and 20 cubs) and 27 males (26 adults and 1 cub) during spring and summer 2015. Using a PCR specific for a mustelid α-HV, all genital-swab samples tested negative. In a panherpes PCR, a γ-HV was found in 55% (54/98; 39 adults and 15 cubs), identified as mustelid gammaherpesvirus 1 (MusGHV-1) using DNA sequencing. This contrasts with the results of a previous study, which reported MusGHV-1 in 98% (354/361) of bl...

Christina D Buesching - One of the best experts on this subject based on the ideXlab platform.

  • patterns of genital tract mustelid gammaherpesvirus 1 musghv 1 reactivation are linked to stressors in european badgers Meles Meles
    Biomolecules, 2021
    Co-Authors: Mingshan Tsai, David W Macdonald, Chris Newman, Sarah Francois, Christina D Buesching
    Abstract:

    Gammaherpesvirus reactivation can promote diseases or impair reproduction. Understanding reactivation patterns and associated risks of different stressors is therefore important. Nevertheless, outside the laboratory or captive environment, studies on the effects of stress on gammaherpesvirus reactivation in wild mammals are lacking. Here we used Mustelid gammaherpesvirus 1 (MusGHV-1) infection in European badgers (Meles Meles) as a host–pathogen wildlife model to study the effects of a variety of demographic, physiological and environmental stressors on virus shedding in the genital tract. We collected 251 genital swabs from 150 free-ranging individuals across three seasons and screened them for the presence of MusGHV-1 DNA using PCR targeting the DNA polymerase gene. We explored possible links between MusGHV-1 DNA presence and seven variables reflecting stressors, using logistic regression analysis. The results reveal different sets of risk factors between juveniles and adults, likely reflecting primary infection and reactivation. In adults, virus shedding was more likely in badgers in poorer body condition and younger than 5 years or older than 7; while in juveniles, virus shedding is more likely in females and individuals in better body condition. However, living in social groups with more cubs was a risk factor for all badgers. We discuss possible explanations for these risk factors and their links to stress in badgers.

  • A non-invasive method to assess the reproductive status of the European badger (Meles Meles) from urinary sex-steroid metabolites
    General and comparative endocrinology, 2020
    Co-Authors: Nadine Adrianna Sugianto, David W Macdonald, Chris Newman, Martin Dehnhard, Christina D Buesching
    Abstract:

    Abstract Due to their unique reproductive physiology and behaviour, European badgers (Meles Meles) are often used as a model to study mammalian reproduction. For reproductive endocrinology, circulating hormone levels are conventionally measured directly from blood samples. However, routine blood sampling is often not practical for wild animals and may induce stress affecting measurement accuracy. Non-invasive alternatives are thus of interest. Circulating hormones are metabolized through different routes, either by the kidneys, to be excreted through urine, or by the liver, to be excreted through faeces. These metabolites can thus be used as a proxy of hormone measurements, provided the species-specific metabolic characteristics are known. Here we tested the suitability of measuring urinary metabolites of circulating plasma sex-steroid hormones (testosterone in males and oestrogen in females) with enzyme immunoassays to assess the reproductive status of the European badger (Meles Meles). Biological validation evidenced that urinary testosterone metabolite (UTM) and urinary total oestrogen metabolite (UEM) excretion patterns both corresponded with seasonal badger reproductive patterns on a population level, signaling correlation over a broad time frame. On an individual level, concurrent sampling of urine and plasma showed that male plasma testosterone and UTM levels correlated significantly across seasons, but no short term correlation was evident for total oestrogen and UEM in females. Thus, in badgers, urinary sex-steroid metabolites can be used reliably in the short term to assess male reproductive status at the individual level, but only at the broader population level for females.

  • effects of mustelid gammaherpesvirus 1 musghv 1 reactivation in european badger Meles Meles genital tracts on reproductive fitness
    Pathogenetics, 2020
    Co-Authors: Mingshan Tsai, Chris Newman, David W Macdonald, Andrew W. Byrne, Ursula Fogarty, James Okeeffe, Christina D Buesching
    Abstract:

    Reactivation of latent Gammaherpesvirus in the genital tract can lead to reproductive failure in domestic animals. Nevertheless, this pathophysiology has not received formal study in wild mammals. High prevalence of Mustelid gammaherpesvirus 1 (MusGHV-1) DNA detected in the genital tracts of European badgers (Meles Meles) implies that this common pathogen may be a sexual transmitted infection. Here we used PCR to test MusGHV-1 DNA prevalence in genital swabs collected from 144 wild badgers in Ireland (71 males, 73 females) to investigate impacts on male fertility indicators (sperm abundance and testes weight) and female fecundity (current reproductive output). MusGHV-1 reactivation had a negative effect on female reproduction, but not on male fertility; however males had a higher risk of MusGHV-1 reactivation than females, especially during the late-winter mating season, and genital MusGHV-1 reactivation differed between age classes, where 3–5 year old adults had significantly lower reactivation rates than younger or older ones. Negative results in foetal tissues from MusGHV-1 positive mothers indicated that cross-placental transmission was unlikely. This study has broader implications for how wide-spread gammaherpesvirus infections could affect reproductive performance in wild Carnivora species.

  • encoded information within urine influences behavioural responses among european badgers Meles Meles
    2019
    Co-Authors: Tanesha M Allen, Chris Newman, David W Macdonald, Nadine Adrianna Sugianto, Charlotte Ryder, Christina D Buesching
    Abstract:

    Metabolic by-products like sex-steroid metabolites convey information regarding an individual’s physiological fitness and reproductive state. Urine and faeces containing these excreted metabolites can function as cues for conspecifics within social contexts, particularly for mate selection. Our pilot study investigated in scent provisioning experiments how donor- and responder-related characteristics influenced behavioural responses towards excreted sex-steroid metabolites. We used 51 urine samples with known urinary hormone concentrations (determined by EIA corrected for specific gravity) collected from known individuals in a high-density population of European badgers ( Meles Meles ) in Wytham Woods, Oxfordshire, UK during the spring mating season. Samples were provided in Eppendorf tubes pushed into the ground near badger setts to assess how response likelihood, sniff duration, and countermarking responses varied according to donor-related traits (age, sex, group familiarity and hormone concentrations). From 143 videos containing 26 identifiable adult responders, we observed adult badgers modifying their behaviour towards urine samples based on the perceived relevance to their own traits with badgers investigating and countermarking urine from opposite-sex donors more often than urine from same-sex donors. This suggests that urine-marking can serve as an adaptive signal for individual advertisement. Additionally, all badgers were more likely to investigate male urine (containing testosterone) than female urine (containing oestradiol); however, no other clear effects of sex-steroid metabolites were noticed. We consider that this could be a feature of the social evolution of badgers or arise because badgers signal reproductive status through other olfactory secretions, notably their unique subcaudal gland marking behaviour.

  • genital tract screening finds widespread infection with mustelid gammaherpesvirus 1 in the european badger Meles Meles
    Journal of Wildlife Diseases, 2018
    Co-Authors: Alice Kent, Chris Newman, David W Macdonald, Bernhard Ehlers, Tom A Mendum, Mark A Chambers, Christina D Buesching
    Abstract:

    ABSTRACT:  Sexually transmitted diseases (STDs) can be important drivers of population dynamics because of their negative effects on reproduction. However, screening for STDs, especially in wildlife populations, is widely neglected. Using the promiscuous, polygynandrous European badger (Meles Meles) as a model, we investigated the presence and prevalence of herpesviruses (HVs) in a wild, high-density population and assessed potential differences in somatic fitness and female reproductive condition between infected and uninfected individuals. We collected n=98 genital swabs from 71 females (51 adults and 20 cubs) and 27 males (26 adults and 1 cub) during spring and summer 2015. Using a PCR specific for a mustelid α-HV, all genital-swab samples tested negative. In a panherpes PCR, a γ-HV was found in 55% (54/98; 39 adults and 15 cubs), identified as mustelid gammaherpesvirus 1 (MusGHV-1) using DNA sequencing. This contrasts with the results of a previous study, which reported MusGHV-1 in 98% (354/361) of bl...

Chris Newman - One of the best experts on this subject based on the ideXlab platform.

  • patterns of genital tract mustelid gammaherpesvirus 1 musghv 1 reactivation are linked to stressors in european badgers Meles Meles
    Biomolecules, 2021
    Co-Authors: Mingshan Tsai, David W Macdonald, Chris Newman, Sarah Francois, Christina D Buesching
    Abstract:

    Gammaherpesvirus reactivation can promote diseases or impair reproduction. Understanding reactivation patterns and associated risks of different stressors is therefore important. Nevertheless, outside the laboratory or captive environment, studies on the effects of stress on gammaherpesvirus reactivation in wild mammals are lacking. Here we used Mustelid gammaherpesvirus 1 (MusGHV-1) infection in European badgers (Meles Meles) as a host–pathogen wildlife model to study the effects of a variety of demographic, physiological and environmental stressors on virus shedding in the genital tract. We collected 251 genital swabs from 150 free-ranging individuals across three seasons and screened them for the presence of MusGHV-1 DNA using PCR targeting the DNA polymerase gene. We explored possible links between MusGHV-1 DNA presence and seven variables reflecting stressors, using logistic regression analysis. The results reveal different sets of risk factors between juveniles and adults, likely reflecting primary infection and reactivation. In adults, virus shedding was more likely in badgers in poorer body condition and younger than 5 years or older than 7; while in juveniles, virus shedding is more likely in females and individuals in better body condition. However, living in social groups with more cubs was a risk factor for all badgers. We discuss possible explanations for these risk factors and their links to stress in badgers.

  • A non-invasive method to assess the reproductive status of the European badger (Meles Meles) from urinary sex-steroid metabolites
    General and comparative endocrinology, 2020
    Co-Authors: Nadine Adrianna Sugianto, David W Macdonald, Chris Newman, Martin Dehnhard, Christina D Buesching
    Abstract:

    Abstract Due to their unique reproductive physiology and behaviour, European badgers (Meles Meles) are often used as a model to study mammalian reproduction. For reproductive endocrinology, circulating hormone levels are conventionally measured directly from blood samples. However, routine blood sampling is often not practical for wild animals and may induce stress affecting measurement accuracy. Non-invasive alternatives are thus of interest. Circulating hormones are metabolized through different routes, either by the kidneys, to be excreted through urine, or by the liver, to be excreted through faeces. These metabolites can thus be used as a proxy of hormone measurements, provided the species-specific metabolic characteristics are known. Here we tested the suitability of measuring urinary metabolites of circulating plasma sex-steroid hormones (testosterone in males and oestrogen in females) with enzyme immunoassays to assess the reproductive status of the European badger (Meles Meles). Biological validation evidenced that urinary testosterone metabolite (UTM) and urinary total oestrogen metabolite (UEM) excretion patterns both corresponded with seasonal badger reproductive patterns on a population level, signaling correlation over a broad time frame. On an individual level, concurrent sampling of urine and plasma showed that male plasma testosterone and UTM levels correlated significantly across seasons, but no short term correlation was evident for total oestrogen and UEM in females. Thus, in badgers, urinary sex-steroid metabolites can be used reliably in the short term to assess male reproductive status at the individual level, but only at the broader population level for females.

  • effects of mustelid gammaherpesvirus 1 musghv 1 reactivation in european badger Meles Meles genital tracts on reproductive fitness
    Pathogenetics, 2020
    Co-Authors: Mingshan Tsai, Chris Newman, David W Macdonald, Andrew W. Byrne, Ursula Fogarty, James Okeeffe, Christina D Buesching
    Abstract:

    Reactivation of latent Gammaherpesvirus in the genital tract can lead to reproductive failure in domestic animals. Nevertheless, this pathophysiology has not received formal study in wild mammals. High prevalence of Mustelid gammaherpesvirus 1 (MusGHV-1) DNA detected in the genital tracts of European badgers (Meles Meles) implies that this common pathogen may be a sexual transmitted infection. Here we used PCR to test MusGHV-1 DNA prevalence in genital swabs collected from 144 wild badgers in Ireland (71 males, 73 females) to investigate impacts on male fertility indicators (sperm abundance and testes weight) and female fecundity (current reproductive output). MusGHV-1 reactivation had a negative effect on female reproduction, but not on male fertility; however males had a higher risk of MusGHV-1 reactivation than females, especially during the late-winter mating season, and genital MusGHV-1 reactivation differed between age classes, where 3–5 year old adults had significantly lower reactivation rates than younger or older ones. Negative results in foetal tissues from MusGHV-1 positive mothers indicated that cross-placental transmission was unlikely. This study has broader implications for how wide-spread gammaherpesvirus infections could affect reproductive performance in wild Carnivora species.

  • encoded information within urine influences behavioural responses among european badgers Meles Meles
    2019
    Co-Authors: Tanesha M Allen, Chris Newman, David W Macdonald, Nadine Adrianna Sugianto, Charlotte Ryder, Christina D Buesching
    Abstract:

    Metabolic by-products like sex-steroid metabolites convey information regarding an individual’s physiological fitness and reproductive state. Urine and faeces containing these excreted metabolites can function as cues for conspecifics within social contexts, particularly for mate selection. Our pilot study investigated in scent provisioning experiments how donor- and responder-related characteristics influenced behavioural responses towards excreted sex-steroid metabolites. We used 51 urine samples with known urinary hormone concentrations (determined by EIA corrected for specific gravity) collected from known individuals in a high-density population of European badgers ( Meles Meles ) in Wytham Woods, Oxfordshire, UK during the spring mating season. Samples were provided in Eppendorf tubes pushed into the ground near badger setts to assess how response likelihood, sniff duration, and countermarking responses varied according to donor-related traits (age, sex, group familiarity and hormone concentrations). From 143 videos containing 26 identifiable adult responders, we observed adult badgers modifying their behaviour towards urine samples based on the perceived relevance to their own traits with badgers investigating and countermarking urine from opposite-sex donors more often than urine from same-sex donors. This suggests that urine-marking can serve as an adaptive signal for individual advertisement. Additionally, all badgers were more likely to investigate male urine (containing testosterone) than female urine (containing oestradiol); however, no other clear effects of sex-steroid metabolites were noticed. We consider that this could be a feature of the social evolution of badgers or arise because badgers signal reproductive status through other olfactory secretions, notably their unique subcaudal gland marking behaviour.

  • genital tract screening finds widespread infection with mustelid gammaherpesvirus 1 in the european badger Meles Meles
    Journal of Wildlife Diseases, 2018
    Co-Authors: Alice Kent, Chris Newman, David W Macdonald, Bernhard Ehlers, Tom A Mendum, Mark A Chambers, Christina D Buesching
    Abstract:

    ABSTRACT:  Sexually transmitted diseases (STDs) can be important drivers of population dynamics because of their negative effects on reproduction. However, screening for STDs, especially in wildlife populations, is widely neglected. Using the promiscuous, polygynandrous European badger (Meles Meles) as a model, we investigated the presence and prevalence of herpesviruses (HVs) in a wild, high-density population and assessed potential differences in somatic fitness and female reproductive condition between infected and uninfected individuals. We collected n=98 genital swabs from 71 females (51 adults and 20 cubs) and 27 males (26 adults and 1 cub) during spring and summer 2015. Using a PCR specific for a mustelid α-HV, all genital-swab samples tested negative. In a panherpes PCR, a γ-HV was found in 55% (54/98; 39 adults and 15 cubs), identified as mustelid gammaherpesvirus 1 (MusGHV-1) using DNA sequencing. This contrasts with the results of a previous study, which reported MusGHV-1 in 98% (354/361) of bl...

Yung Wa Sin - One of the best experts on this subject based on the ideXlab platform.

  • coding of group odor in the subcaudal gland secretion of the european badger Meles Meles chemical composition and pouch microbiota
    2016
    Co-Authors: Christina D Buesching, Terry Burke, Yung Wa Sin, Veronica H Tinnesand, Frank Rosell, David W Macdonald
    Abstract:

    The fermentation hypothesis predicts that odor profiles of mammals depend partly on the primary gland products excreted by the animal and partly on the composition of the bacterial flora converting these into secondary metabolites. Some mammalian odors, such as shared group odors, however, need to be consistent yet flexible (e.g., to allow for changes in social-group affiliation), and are thus predisposed for microbial mediation. Using terminal restriction fragment (TRF) length polymorphism analyses we analyzed the microbial community in subcaudal-gland secretions of European badgers (Meles Meles) in relation to the chemical scent profiles as determined by gas chromatography-mass spectrometry analyses (GCMS) of 66 adults belonging to six different social groups. We found a total of 50 TRFs and 125 different chemical compounds with a subset of four TRFs best explaining the structure in the chemical matrix. Nevertheless, although semiochemical profiles were group specific, microbial profiles were not. In our approach, however, the number of operational taxonomic units exceeded the numbers of TRFs, and thus our analyses were likely limited by the afforded resolution. As it is likely that the variation in metabolic activity is found at the species-, subspecies-, or even strain-level, future high-throughput sequencing can be expected to reveal more subtle differences in the microbial communities between social groups.

  • mhc class ii assortative mate choice in european badgers Meles Meles
    Molecular Ecology, 2015
    Co-Authors: Christina D Buesching, Chris Newman, Geetha Annavi, Terry Burke, Yung Wa Sin, David W Macdonald
    Abstract:

    The major histocompatibility complex (MHC) plays a crucial role in the immune system, and in some species, it is a target by which individuals choose mates to optimize the fitness of their offspring, potentially mediated by olfactory cues. Under the genetic compatibility hypothesis, individuals are predicted to choose mates with compatible MHC alleles, to increase the fitness of their offspring. Studies of MHC-based mate choice in wild mammals are under-represented currently, and few investigate more than one class of MHC genes. We investigated mate choice based on the compatibility of MHC class I and II genes in a wild population of European badgers (Meles Meles). We also investigated mate choice based on microsatellite-derived pairwise relatedness, to attempt to distinguish MHC-specific effects from genomewide effects. We found MHC-assortative mating, based on MHC class II, but not class I genes. Parent pairs had smaller MHC class II DRB amino acid distances and smaller functional distances than expected from random pairings. When we separated the analyses into within-group and neighbouring-group parent pairs, only neighbouring-group pairs showed MHC-assortative mating, due to similarity at MHC class II loci. Our randomizations showed no evidence of genomewide-based inbreeding, based on 35 microsatellite loci; MHC class II similarity was therefore the apparent target of mate choice. We propose that MHC-assortative mate choice may be a local adaptation to endemic pathogens, and this assortative mate choice may have contributed to the low MHC genetic diversity in this population.

  • pathogen burden co infection and major histocompatibility complex variability in the european badger Meles Meles
    Molecular Ecology, 2014
    Co-Authors: Chris Newman, Hannah L Dugdale, Geetha Annavi, Yung Wa Sin, Terry Burke
    Abstract:

    Pathogen-mediated selection is thought to maintain the extreme diversity in the major histocompatibility complex (MHC) genes, operating through the heterozygote advantage, rare-allele advantage and fluctuating selection mechanisms. Heterozygote advantage (i.e. recognizing and binding a wider range of antigens than homozygotes) is expected to be more detectable when multiple pathogens are considered simultaneously. Here, we test whether MHC diversity in a wild population of European badgers (Meles Meles) is driven by pathogen-mediated selection. We examined individual prevalence (infected or not), infection intensity and co-infection of 13 pathogens from a range of taxa and examined their relationships with MHC class I and class II variability. This population has a variable, but relatively low, number of MHC alleles and is infected by a variety of naturally occurring pathogens, making it very suitable for the investigation of MHC-pathogen relationships. We found associations between pathogen infections and specific MHC haplotypes and alleles. Co-infection status was not correlated with MHC heterozygosity, but there was evidence of heterozygote advantage against individual pathogen infections. This suggests that rare-allele advantages and/or fluctuating selection, and heterozygote advantage are probably the selective forces shaping MHC diversity in this species. We show stronger evidence for MHC associations with infection intensity than for prevalence and conclude that examining both pathogen prevalence and infection intensity is important. Moreover, examination of a large number and diversity of pathogens, and both MHC class I and II genes (which have different functions), provide an improved understanding of the mechanisms driving MHC diversity.

  • an example of life history antecedence in the european badger Meles Meles rapid development of juvenile antioxidant capacity from plasma vitamin e analogue
    Ethology Ecology & Evolution, 2013
    Co-Authors: Kirstin Bilham, Christina D Buesching, Chris Newman, Yung Wa Sin, David W Macdonald
    Abstract:

    The way organisms cope with oxidative stress, to quench potentially toxic oxygen free radicals while maintaining oxygen species functionality, is crucial in shaping life-history traits. Antioxidant capacity plays an important role in this process. Here we use multi-model inference procedures to examine the age-class-dependent non-enzymatic antioxidant capacity of the European badger (Meles Meles), testing non-enzymatic plasma antioxidant capacity and expressing the results as vitamin E analogue (VEA) equivalent units. Despite immaturity (ca 16 weeks old), cubs exhibited plasma antioxidant capacity equivalent to those of prime-age adults (1–5 years old). Compared to individuals aged 6 years and over, cubs exhibited significantly higher non-enzymatic plasma antioxidant capacity. There was no association between plasma antioxidant capacity and sex or other physiological variables, such as body condition or presence of wounding. We consider the adaptive significance of this life-history strategy with respect ...

  • evolution of mhc class i genes in the european badger Meles Meles
    Ecology and Evolution, 2012
    Co-Authors: Chris Newman, David W Macdonald, Hannah L Dugdale, Yung Wa Sin, Terry Burke
    Abstract:

    The major histocompatibility complex (MHC) plays a central role in the adaptive immune system and provides a good model with which to understand the evolutionary processes underlying functional genes. Trans-species polymorphism and orthology are both commonly found in MHC genes; however, mammalian MHC class I genes tend to cluster by species. Concerted evolution has the potential to homogenize different loci, whereas birth-and-death evolution can lead to the loss of orthologs; both processes result in monophyletic groups within species. Studies investigating the evolution of MHC class I genes have been biased toward a few particular taxa and model species. We present the first study of MHC class I genes in a species from the superfamily Musteloidea. The European badger (Meles Meles) exhibits moderate variation in MHC class I sequences when compared to other carnivores. We identified seven putatively functional sequences and nine pseudogenes from genomic (gDNA) and complementary (cDNA) DNA, signifying at least two functional class I loci. We found evidence for separate evolutionary histories of the α1 and α2/α3 domains. In the α1 domain, several sequences from different species were more closely related to each other than to sequences from the same species, resembling orthology or trans-species polymorphism. Balancing selection and probable recombination maintain genetic diversity in the α1 domain, evidenced by the detection of positive selection and a recombination event. By comparison, two recombination breakpoints indicate that the α2/α3 domains have most likely undergone concerted evolution, where recombination has homogenized the α2/α3 domains between genes, leading to species-specific clusters of sequences. Our findings highlight the importance of analyzing MHC domains separately.

Terry Burke - One of the best experts on this subject based on the ideXlab platform.

  • coding of group odor in the subcaudal gland secretion of the european badger Meles Meles chemical composition and pouch microbiota
    2016
    Co-Authors: Christina D Buesching, Terry Burke, Yung Wa Sin, Veronica H Tinnesand, Frank Rosell, David W Macdonald
    Abstract:

    The fermentation hypothesis predicts that odor profiles of mammals depend partly on the primary gland products excreted by the animal and partly on the composition of the bacterial flora converting these into secondary metabolites. Some mammalian odors, such as shared group odors, however, need to be consistent yet flexible (e.g., to allow for changes in social-group affiliation), and are thus predisposed for microbial mediation. Using terminal restriction fragment (TRF) length polymorphism analyses we analyzed the microbial community in subcaudal-gland secretions of European badgers (Meles Meles) in relation to the chemical scent profiles as determined by gas chromatography-mass spectrometry analyses (GCMS) of 66 adults belonging to six different social groups. We found a total of 50 TRFs and 125 different chemical compounds with a subset of four TRFs best explaining the structure in the chemical matrix. Nevertheless, although semiochemical profiles were group specific, microbial profiles were not. In our approach, however, the number of operational taxonomic units exceeded the numbers of TRFs, and thus our analyses were likely limited by the afforded resolution. As it is likely that the variation in metabolic activity is found at the species-, subspecies-, or even strain-level, future high-throughput sequencing can be expected to reveal more subtle differences in the microbial communities between social groups.

  • mhc class ii assortative mate choice in european badgers Meles Meles
    Molecular Ecology, 2015
    Co-Authors: Christina D Buesching, Chris Newman, Geetha Annavi, Terry Burke, Yung Wa Sin, David W Macdonald
    Abstract:

    The major histocompatibility complex (MHC) plays a crucial role in the immune system, and in some species, it is a target by which individuals choose mates to optimize the fitness of their offspring, potentially mediated by olfactory cues. Under the genetic compatibility hypothesis, individuals are predicted to choose mates with compatible MHC alleles, to increase the fitness of their offspring. Studies of MHC-based mate choice in wild mammals are under-represented currently, and few investigate more than one class of MHC genes. We investigated mate choice based on the compatibility of MHC class I and II genes in a wild population of European badgers (Meles Meles). We also investigated mate choice based on microsatellite-derived pairwise relatedness, to attempt to distinguish MHC-specific effects from genomewide effects. We found MHC-assortative mating, based on MHC class II, but not class I genes. Parent pairs had smaller MHC class II DRB amino acid distances and smaller functional distances than expected from random pairings. When we separated the analyses into within-group and neighbouring-group parent pairs, only neighbouring-group pairs showed MHC-assortative mating, due to similarity at MHC class II loci. Our randomizations showed no evidence of genomewide-based inbreeding, based on 35 microsatellite loci; MHC class II similarity was therefore the apparent target of mate choice. We propose that MHC-assortative mate choice may be a local adaptation to endemic pathogens, and this assortative mate choice may have contributed to the low MHC genetic diversity in this population.

  • pathogen burden co infection and major histocompatibility complex variability in the european badger Meles Meles
    Molecular Ecology, 2014
    Co-Authors: Chris Newman, Hannah L Dugdale, Geetha Annavi, Yung Wa Sin, Terry Burke
    Abstract:

    Pathogen-mediated selection is thought to maintain the extreme diversity in the major histocompatibility complex (MHC) genes, operating through the heterozygote advantage, rare-allele advantage and fluctuating selection mechanisms. Heterozygote advantage (i.e. recognizing and binding a wider range of antigens than homozygotes) is expected to be more detectable when multiple pathogens are considered simultaneously. Here, we test whether MHC diversity in a wild population of European badgers (Meles Meles) is driven by pathogen-mediated selection. We examined individual prevalence (infected or not), infection intensity and co-infection of 13 pathogens from a range of taxa and examined their relationships with MHC class I and class II variability. This population has a variable, but relatively low, number of MHC alleles and is infected by a variety of naturally occurring pathogens, making it very suitable for the investigation of MHC-pathogen relationships. We found associations between pathogen infections and specific MHC haplotypes and alleles. Co-infection status was not correlated with MHC heterozygosity, but there was evidence of heterozygote advantage against individual pathogen infections. This suggests that rare-allele advantages and/or fluctuating selection, and heterozygote advantage are probably the selective forces shaping MHC diversity in this species. We show stronger evidence for MHC associations with infection intensity than for prevalence and conclude that examining both pathogen prevalence and infection intensity is important. Moreover, examination of a large number and diversity of pathogens, and both MHC class I and II genes (which have different functions), provide an improved understanding of the mechanisms driving MHC diversity.

  • evolution of mhc class i genes in the european badger Meles Meles
    Ecology and Evolution, 2012
    Co-Authors: Chris Newman, David W Macdonald, Hannah L Dugdale, Yung Wa Sin, Terry Burke
    Abstract:

    The major histocompatibility complex (MHC) plays a central role in the adaptive immune system and provides a good model with which to understand the evolutionary processes underlying functional genes. Trans-species polymorphism and orthology are both commonly found in MHC genes; however, mammalian MHC class I genes tend to cluster by species. Concerted evolution has the potential to homogenize different loci, whereas birth-and-death evolution can lead to the loss of orthologs; both processes result in monophyletic groups within species. Studies investigating the evolution of MHC class I genes have been biased toward a few particular taxa and model species. We present the first study of MHC class I genes in a species from the superfamily Musteloidea. The European badger (Meles Meles) exhibits moderate variation in MHC class I sequences when compared to other carnivores. We identified seven putatively functional sequences and nine pseudogenes from genomic (gDNA) and complementary (cDNA) DNA, signifying at least two functional class I loci. We found evidence for separate evolutionary histories of the α1 and α2/α3 domains. In the α1 domain, several sequences from different species were more closely related to each other than to sequences from the same species, resembling orthology or trans-species polymorphism. Balancing selection and probable recombination maintain genetic diversity in the α1 domain, evidenced by the detection of positive selection and a recombination event. By comparison, two recombination breakpoints indicate that the α2/α3 domains have most likely undergone concerted evolution, where recombination has homogenized the α2/α3 domains between genes, leading to species-specific clusters of sequences. Our findings highlight the importance of analyzing MHC domains separately.

  • Molecular characterization of the microbial communities in the subcaudal gland secretion of the European badger (Meles Meles).
    FEMS microbiology ecology, 2012
    Co-Authors: Yung Wa Sin, Christina D Buesching, Terry Burke, David W Macdonald
    Abstract:

    Many mammals possess specialized scent glands, which convey information about the marking individual. As the chemical profile of scent marks is likely to be affected by bacteria metabolizing the primary gland products, the variation in bacterial communities between different individuals has been proposed to underpin olfactory communication. However, few studies have investigated the dependency of microbiota residing in the scent organs on the host's individual-specific parameters. Here, we used terminal restriction fragment length polymorphism analysis of the PCR-amplified 16S rRNA gene and clone library construction to investigate the microbial communities in the subcaudal gland secretion of the European badger (Meles Meles). As the secretion has been shown to encode individual-specific information, we investigated the correlation of the microbiota with different individual-specific parameters (age, sex, body condition, reproductive status, and season). We discovered a high number of bacterial species (56 operational taxonomic units from four phyla: Actinobacteria, Firmicutes, Proteobacteria, and Bacteroidetes), dominated by Actinobacteria (76.0%). The bacterial communities of cubs and adults differed significantly. Cubs possessed considerably more diverse communities dominated by Firmicutes, while in adults the communities were less diverse and dominated by Actinobacteria, suggesting that the acquisition of a 'mature bacterial community' is an ontogenetic process related to physiological changes during maturation.