FECAL PROGESTAGEN EVALUATIONS TO MONITOR THE ESTROUS-CYCLE AND PREGNANCY IN THE OKAPI (OKAPIA-JOHNSTONI)

The present study was conducted to establish a noninvasive method of r eproductive monitoring in the okapi (Okapia johnstoni). Fecal samples were collected three times a week from nonpregnant okapis (n = 3) for periods of 2, 9, and 23 months, respectively, and for 2 months each fr om pregnant okapis (n = 4) at different stages of gestation. Samples w ere analyzed with an enzyme-immunoassay (EIA), using an antibody again st pregnanediol, and the results are considered as measurements of unc onjugated total immunoreactive progestagens (Pd-Pgs). Mean values of P d-Pgs during the follicular (FP) and the luteal phases (LP) of the est rous cycles were 0.6 +/- 0.1 mu g/g and 6.1 +/- 0.3 mu g/g feces, resp ectively. Matings occurred at the terminations of the LP. By dividing the number of entire LPs into the time over which samples were availab le, average estrous cycle lengths in two okapis were estimated to be 1 5.5 (n = 11 LP) and 15.8 (n = 36 LP) days, respectively. In three anim als, gestation lengths of 423, 424, and 431 days were calculated by ob served matings. During days -280 to -220 before parturition, the fecal Pd-Pgs constantly increased from about 20-60 mu g/g feces. Values wer e 100-350 mu g/g during the last third of gestation. Values decreased in the week before parturition, and a continuous decline to FP values was observed within 3-4 days postpartum. During the 2 months postpartu m investigated in one animal, the Pd-Pgs were in the FP range except o ne LP 3 weeks postpartum. It was concluded that fecal Pd-Pgs in female okapis are present in a ratio of similar to 1: 10:>100 during FP, LP, and late pregnancy, respectively. Their measurement by EIA enables no ninvasive monitoring of the estrous cycle and pregnancy diagnosis. (C) 1993 Wiley-Liss, Inc.