Abstract:
Gonadal hormones play a central role in reproductive function and success. As such, quantifying reproductive hormones noninvasively in threatened, vulnerable and endangered wildlife species offers an ideal tool for assessing general and individual
reproductive patterns in situ. Whilst the use of faeces as a hormone matrix is often preferred in these cases, the required enzyme
immunoassays (EIAs) for measuring faecal androgen (fAM), oestrogen (fEM) and progestagen metabolite (fPM) concentrations
must first be validated if a species gets investigated for the first time to ensure biologically relevant patterns can be observed. In
this study we aimed to biologically validate the EIAs for monitoring fAM, fEM and fPM concentrations in Temminck’s pangolin,
Smutsia temminckii. Hormone metabolite concentrations derived from each EIA tested were compared between different
age and sex classes. An epiandrosterone EIA effectively measured androgen levels in males, distinguishing between adult
and juvenile individuals, as well as both female age classes. Similarly, the tested oestrogen EIA successfully distinguished
between adult and juvenile female fEM concentrations, and both tested progestagen EIAs demonstrated adequate differences
between fPM concentrations of adult and juvenile females. The now-validated EIAs offer robust tools for a non-invasive
monitoring of reproductive activity in Temminck’s pangolin. The development of such techniques will allow researchers to
assess reproductive hormone patterns of the species in situ, whilst also paving the way for further studies in this field. Despite
the small sample size due to the species’ conservation status, the study provides a foundation for future research using a
robust, validated, non-invasive monitoring tool. The latter can now be implemented in long-term monitoring with larger
sample sizes to yield more comprehensive data, aiding in the conservation of Temminck’s pangolin.
LAY SUMMARY: Gonadal hormones are crucial for mammalian reproduction. Monitoring these hormones non-invasively in
vulnerable species like Temminck’s pangolin will enhance our understanding of in situ reproductive patterns of pangolin. This
study validated methods to non-invasively measure hormone levels in male and female pangolin faeces.
