Understanding pregnancy-related hormones in female red pandas

Abstract

Non-invasive techniques utilizing fecal samples to measure circulating steroid hormones have proven to effectively reflect the reproductive status of numerous species. Fecal progesterone metabolite (FPM) profiles have enhanced our understanding of the complicated reproductive strategies of many endangered species; however, this tool has been proven to not be optimal for pregnancy detection in the red panda (Ailurus fulgens). This study set out to investigate potential differences in FPM profiles (phases and lengths of hormone elevation) of seven female red pandas, both parturient and non-parturient, confirming FPM analysis is not a valuable indicator of pregnancy in this species. Secondly, examined whether a pregnancy related hormone, prostaglandin F2α and its metabolites (PGFM), can provide a reliable tool for confirming pregnancy in this species. Similarly, PGFM did not differentiate between parturient and non-parturient females until a significant peak the day of parturition (± 2 days). Interestingly, this is the first study to capture the PGFM surge associated with parturition, which may provide a tool for determining pregnancy in cases where live cubs were not observed.