Assessment of the reproductive physiology of the potto (Perodicticus potto) through fecal hormone metabolite analyses and trans-abdominal ultrasonography

Abstract

Potto (Perodicticus potto) reproductive biology has been minimally studied. Noninvasive endocrinology and ultrasonography are proven tools for reproductive assessment in other primates. In this study, we used fecal hormone metabolite analysis to monitor one adult male potto and four females at different life stages. Validated testosterone (T), estrone conjugate (EC), and progesterone (P4) enzyme immunoassays (EIA) were used to assess male testicular function and female ovarian and placental activity. The male excreted mean T concentrations of 4.72 (±1.66) μg/g feces, that did not differ (P > 0.05) over time or when paired with alternate females. Baseline concentrations of EC (range: 47.93-78.81 ng/g feces) and P4 (range: 2.29-12.46 μg/g feces) differed among adult females. Follicular phases averaged 9.1 days (±3.43, n = 30 phases), whereas luteal phases averaged 19.89 days (±9.49, n = 19 phases). Gestation length (n = 2 pregnancies) was 170 days. Gestational EC and P4 concentrations were positively correlated (pregnancy A, r (132) = 0.71; pregnancy B, r (145) = 0.76) and returned to non-pregnant luteal phase levels 3-7 days post parturition. Extreme differences between pregnant and non-pregnant EC and P4 concentrations may allow for one-sample pregnancy diagnosis. Trans-abdominal ultrasonography was validated for pregnancy diagnosis with the fetus observed between 100 and 110 days post breeding. To our knowledge, this is the first use of fecal endocrinology and ultrasonography to monitor reproductive function and pregnancy in this species, and the only study in any lorisid to measure progestagens in correlation with reproductive events.