Physical and behavioral indicators associated with hormonal changes during musth in zoo-housed and free-ranging Asian elephants (Elephas maximus)
In-situ and ex-situ Asian elephant populations are threatened with extinction, and male elephants pose unique challenges to long-term sustainability. The heightened sexual state of “musth” is accompanied by a suite of physical, behavioral and physiological changes. Furthermore, musth is unique to male elephants and requires special consideration when developing short- and long-term management strategies for […]
Monitoring the behaviour and stress physiology of male gorillas Gorilla gorilla gorilla for one year following bachelor group formation
Gorillas Gorilla gorilla gorilla are polygynous so zoos are challenged to provide lifelong socialisation for males not living in mixed-sex or breeding troops. One approach is to establish and manage all-male “bachelor” groups; however, there is little published information on the behavioural and physiological impacts that group formation may have on these individuals. Therefore, we […]
Measurement of Fecal Testosterone Metabolites in Mice: Replacement of Invasive Techniques
Testosterone is the main reproductive hormone in male vertebrates and conventional methods to measure testosterone rely on invasive blood sampling procedures. Here, we aimed to establish a non-invasive alternative by assessing testosterone metabolites (TMs) in fecal and urinary samples in mice. We performed a radiometabolism study to determine the effects of daytime and sex on […]
Longitudinal monitoring of fecal testosterone in male Malayan Sun bears (U. malayanus)
Abstract 10.1002/zoo.20061.abs Fecal steroid monitoring was applied as a non-invasive method to investigate testicular cycles and seasonality in the Malayan Sun bear (Ursus malayanus), an endangered ursid from South East Asia. Fecal testosterone was analyzed by radioimmunoassay in samples collected from male Sun bears (n=8) housed in zoological parks in North America and New Zealand, […]
Use of salivary steroid analyses to assess ovarian cycles in an Indian rhinoceros at the National Zoological Park
Abstract 10.1002/zoo.20028.abs Saliva samples were collected from a female Indian rhinoceros (Rhinoceros unicornis) housed at the National Zoological Park, and ether-extracted for analyses of androgen, estrogen, and progestin metabolites to assess ovarian cycles. Analyses of both salivary androgens and estrogens were found to reliably monitor follicular activity. Although the temporal patterns of the two steroids […]
Reproductive endocrine responses to photoperiod and exogenous gonadotropins in the pallas’ cat (Otocolobus manul)
Abstract Fecal samples were collected for 14–26 months from three male and six female Pallas’ cats (Otocolobus manul) to examine gonadal steroidogenic activity in response to changes in photoperiod and treatment with exogenous gonadotropins. Females exhibited a seasonal anestrus from May–December, excreting consistently low concentrations of fecal estrogens (overall mean, 50.2±8.5 ng/g). During the breeding […]
Comparative analysis of gonadal and adrenal activity in the black and white rhinoceros in North America by noninvasive endocrine monitoring
Abstract 10.1002/zoo.10028.abs Patterns of fecal reproductive steroid metabolites and adrenal corticoids were characterized for 12- to 24-month periods in black (n = 10 male, 16 female) and white (n = 6 male, 13 female) rhinoceroses at 14 institutions. All black rhinoceros females exhibited at least some ovarian cyclicity on the basis of fecal progestogen analysis […]
Environmental modulation of androgen levels and secondary sex characters in two populations of the peacock blenny Salaria pavo
Morphology and endocrinology were studied in two populations of the peacock blenny Salaria pavo, with different regimes of sexual selection imposed by differences in nest site availability. The peacock blenny is a small, sexually dimorphic benthic fish that presents exclusive paternal care of the clutch and inhabits rocky shores of the Mediterranean and adjacent Atlantic […]
Fecal androgens of bison bulls during the rut
The influence of sex hormones is a key proximate factor underlying male reproductive behavior in mammals. Effective conservation policies for the remaining purebred plains bison (Bison bison bison) herds require knowledge of the physiology underlying bison reproductive biology. We used fecal steroid analysis to characterize androgen levels in adult bison bulls before, during, and after […]
Habituation to humans affects yolk steroid levels and offspring phenotype in quail
In the field as well as in the laboratory, human-generated stress responses are reduced in adult animals previously habituated to humans in comparison to non-habituated individuals. In birds, yolk steroid levels vary with maternal environment and condition. We tested the hypothesis that the experience of female birds with humans could affect yolk steroids levels and […]