Ovarian cycle of the captive formosan gem-faced civets (Paguma larvata taivana).

Formosan gem-faced civets are classified to be endemic sub-species of Paguma larvata in Taiwan. Little about their reproductive physiology has been reported. This study was designed to characterize the ovarian activity throughout the year and define ovarian cycle length and the lengths of its component phases. Serum samples were collected for enzyme immunoassay (progesterone and estradiol) from seven captive civets twice weekly for 1 year. Meanwhile, periodic changes in external genitalia (vulva swelling) and vaginal cytology were examined and recorded. Results showed estrous cycles exhibited two types: 18-day (18.5+/-1.1, n=64) and 28-day (27.6+/-1.0, n=28) as shown by progesterone and estradiol fluctuations and corresponding changes in vulva morphology and vaginal cytology. Both types showed a similar 7-day follicular phase, peaking progesterone at Day 7. The 18-day cycle type prevails in the spring and summer whereas the 28-day cycle type is significant in the autumn. In summary, female gem-faced civets are polyestrous (approximately 13 cycles/year), and non-typical seasonal breeders, with follicular phase and two distinct durations of luteal phases (diestrus) cycling throughout the year, but the frequency of ovarian cycles was remarkably gradually decreased from September to February of next year. Zoo Biol 0:1-11, 2007. (c) 2007 Wiley-Liss, Inc.