Reproductive Behavior and Hormone Metabolite Profiles in Captive Breeding Female Sumatran Slow Lorises (Nycticebus hilleri)

A study of the reproductive behavior of the sumatran slow loris (Nycticebus hilleri), along with measurements of estrone conjugate (E1C) and pregnanediol-3-glucuronide (PdG) metabolite hormone levels in feces, was performed as a success parameter of ex-situ conservation in the breeding facility. Behaviors of two adult female N. hilleri (K2 and K5) were observed in their cages from 17:00 to 05:00 WIB from September to November 2015. Feces were collected during the observation period and the levels of E1C and PdG were analyzed by enzyme-linked immunosorbent assay (ELISA). Our results showed that the average percentage of behavior observations (K2 and K5), namely was behavior moving 61%, unseen 15%, resting 8%, social behavior 8%, autogrooming 5%, feeding 4%, and reproductive behavior (1%). The presence of reproductive behaviors (1%), such as sniffing and licking the genitalia of a mate, indicates pair harmony that could lead to copulation. Although copulation was not clearly observed, the presence of unseen behavior (15%) when lorises were in sleeping cages maybe a time when copulation occurred. The highest E1C concentration was 1181.18 pg/g for K2 and 919.93 pg/g for K5. The lowest E1C was 5.75 pg/g for K2 and 29.95 pg/g for K5. The highest PdG was 19995.81 pg/g for K2 and 18168.68 pg/g for K5. The lowest PdG was 20.85 pg/g for K2 and 504.97 pg/g for K5.