REPRODUCTION IN CAPTIVE TAIWAN MACAQUES (MACACA-CYCLOPIS) IN COMPARISON TO OTHER COMMON MACAQUE SPECIES

Twenty-five years of reproductive and birth data from a Macaca cyclopi s colony at the New England Regional Primate Research Center (NERPRC) indicate that these animals are seasonal breeders with a birth peak be tween February and May. Interbirth intervals have a mean of 587.5 +/- 56.6 days. The age at first reproduction for females is 5.08 +/- .357 years and for males 5.01 +/- .94. The normal menstrual cycle length ra nges from 24-31 (mean 27.9 +/- .506) days, with ''off-season'' long cy cles ranging from 43-69 days. For 10 females studied prospectively, th e sex skin color cycle ranged from 23-34 days and exhibited no long cy cles. The peak estradiol value was 1.35 nmol/L on day 11 (range 10-12) of the menstrual cycle. Estradiol values ranged from 0.7-2.0 nmol/L. The peak progesterone value was 23 nmol/L on day 21 (17-23). Progester one levels ranged from 10-42 nmol/L. The observed lower fecundability of M. cyclopis in a timed mating program is consistent with later ages at first reproduction and longer interbirth compared to the other spe cies in breeding colonies at NERPRC. (C) 1995 Wiley-Liss, Inc.