Seasonal variations in plasma luteinizing hormone and testosterone levels in the European badger Meles meles L

Seasonal variation in daily patterns of social contacts in the European badger Meles meles

“…Badgers tend to be in better body condition during winter than in summer (Rogers et al., ). Changes in hormones that might alter immuno‐competence and susceptibility also provide mixed evidence, as although testosterone in males peaks in late winter (Audy et al., ), levels of cortisol show spring or summer peaks and are negatively correlated with body condition (George et al., ). There is currently more compelling evidence to support an increase in M. bovis exposure risk driven by seasonal changes in badger behavior, given that the empirical data available point toward neither stress physiology or body condition providing a likely explanation.…”

“…We also anticipated that seasonal variation in contact patterns might be correlated with seasonal differences in the likelihood of individuals becoming infected (Gallagher & Clifton‐Hadley, ; Buzdugan, Vergne, Grosbois, Delahay, & Drewe, ). It is likely that there is additional seasonal variation in individual state among these same periods (e.g., Audy et al., ; George, Smith, Mac Cana, Coleman, & Montgomery, ; Rogers, Cheeseman, & Langton, ), and we acknowledge that other factors such as this may play additional roles. More specifically, we predicted that social contacts would be less frequent in the spring when females have dependent cubs (Roper, ) and males are engaged in territorial behavior (Roper et al., ) than in other seasons, particularly as a similar pattern had been previously demonstrated in a medium‐density population of badgers (O'Mahony, ).…”

Seasonal changes in plasma concentrations of gonadotropins and in the responsiveness of the pituitary and testis to GnRH in a desert rodent, the sand rat (Psammomys obesus)

“…Because of the very low plasma values at 0 min, the purification on celite column was omitted (Khammar and Brudieux, 1987 Schanbacher and Lunstra, 1976;Ortavant and Loir, 1980) and in wild animals (vole: Charlton et al, 1983;mongoose: Soares and Hoffmann, 1981;squirrel: Barnes, 1986; fox and badger: Maurel, 1981;Audy et al, 1985;deer: Lincoln and Kay, 1979;Bubenik et al, 1982). In most cases, seasonal changes in plasma LH levels parallelled those of plasma testosterone concentrations.…”