Female teat size is a reliable indicator of annual breeding success in European badgers: Genetic validation

Abstract

Researchers have applied teat measurements previously to assess whether females, in a 4 variety of mammalian species, have bred; however, this technique has not been validated 5 genetically. Furthermore, several analytical techniques are available to classify 6 individuals, but their misclassification rates have not been compared. We used 22 7 microsatellite loci to assign maternity, with 95% confidence, within a high-density 8 population of European badgers Meles meles, as plural and subterranean breeding means 9 that maternity cannot be inferred from behavioural observations. The teat lengths and 10 diameters of 136 females, measured May-July 1994-2005, from social groups in which 11 all offspring were assigned a mother, were reliable indicators of recent breeding success. 12 A Generalised Linear Mixed Model (GLMM) classified both breeding and non-breeding 13 females with lower error rates than discriminant analyses and crude teat-size criteria. The 14 GLMM model logit probability = -20 + 1.8 month + 1.6 mean teat length + 1.0 mean 15 teat diameter can be applied quickly in the field to assess the probability with which a 16 female badger should be assigned maternity. This is a low-cost measure which, after 17 validation, could be used in other badger or mammalian populations to assess the 18 breeding success of females. This may be a particularly useful welfare tool for veterinary 19 practitioners, especially during badger culls. 20 21

Genital Tract Screening Finds Widespread Infection With Mustelid Gammaherpesvirus 1 in the European Badger (Meles Meles)

“…Age (categorized as cub: ,1 yr; yearling: ,2 yr, sexually immature; adult: !2 yr), social group, body condition (categorized as 1¼emaciated to 5¼very good condition), and female reproductive status (classified as estrus: vulva swollen and moist; nonestrus: vulva flat and dry) were recorded. Reproductive success was inferred from teat size and recent lactation (Dugdale et al 2011), corroborated by genetic pedigree for the study year, enabling assessment of current and subsequent reproductive success in the following breeding season.…”

Latrine marking patterns of badgers (Meles meles) with respect to population density and range size

“…, Wytham Woods: Dugdale et al. , ). In WW, approximately 48% of cubs are fathered by extraterritorial males, the majority (approximately 86%) from neighboring groups, but also from more distant liaisons (Dugdale et al.…”

Avoiding verisimilitude when modelling ecological responses to climate change: the influence of weather conditions on trapping efficiency in European badgers (Meles meles)

“…This leads to a very restricted availability, limiting trap success to the extent that we only conduct winter trapping on an ‘ ad hoc ’ basis to include mostly favourable conditions. Elaborating on our previous findings that cub cohort size extrapolated from ultrasound performed on females caught in January does not account for the actual annual cohort size adequately (Dugdale et al ., ), we speculate that this is misrepresentative due to these being thinner, more desperate and trappable pregnant mothers with sub‐average embryonic litter sizes. This elucidates the complexities of climate‐mediated variation in trappability, because poor conditions that lead to high TE will bias population estimates positively, while they simultaneously drive actual population size down.…”

“…Furthermore, our previous work has exposed facets of interactions with seasonal weather patterns that have stimulated us to evaluate more precisely how badgers respond to climatic conditions. For example, extrapolating the mean litter size observed among females caught in January and diagnosed with ultrasound (Woodroffe, ) onto the subsequent number of lactating females (Dugdale et al ., ) does not adequately account for the actual annual cohort size. This would only be explained if those females trapped in January are not truly representative of mean litter size.…”