2010 Volume 15 Issue 2 Pages 49-55
Using enzyme immunoassays, estradiol-17β(E2) and progesterone (P4) levels were measured in urine samples collected dairy from 2 female captive Bornean orangutans (Pongo pygmaeus). Mean menstrual cycles, and the length of follicular phases in one female (#1) were significantly shorter than those in the other female (#2) (mean±SEM, 17.2± 0.6 vs. 12.8± 0.5 days). On the other hand, the length of luteal phases was not significantly different between the 2 females (13.7± 0.4 vs. 12.0± 0.9 days). Based on the results of hormonal analysis, the 2 females were introduced to a male around the day of the E2 peak, and were successfully mated. Pregnancies were confirmed using a hCG kit. During pregnancies, both females showed a similar pattern of increase in levels of both of P4 and E2. In the female #1, both hormones peaked around the 31st to 32nd weeks of gestation and then decreased. This female gave birth to a male baby 238 days after the final copulation. The female #2 is in the gestational currently.
