COMBINED SERIAL ULTRASONOGRAPHY AND FECAL PROGESTIN ANALYSIS FOR REPRODUCTIVE EVALUATION OF THE FEMALE WHITE RHINOCEROS (CERATOTHERIUM-SIMUM SIMUM) - PRELIMINARY-RESULTS

Ultrasonographic examinations of one multiparous 33-year-old female so uthern white rhinoceros (Ceratotherium simum simum) resulted in docume ntation of the animal's estrous cycle, elucidation of the timing of ov ulation in relation to estrus, and ultrasonographic evidence of endome tritis and associated early embryonic death. The preovulatory follicle was observed to change in shape from spherical to pear-shape (n = 3) and to reach a mean follicular diameter of similar to 30 mm (n = 4) in the 48 hr preceding estrus, An ovulation site in the location of the preovulatory follicle was observed to occur within 24 hr postbreeding on one occasion. Both pregnancies monitored in this female in 1995 wer e lost by day 28 postovulation, with collapse of the embryonic vesicle documented via ultrasound. Ultrasonographic evidence of endometritis was observed in this female and was characterized by small quantities of anechoic intrauterine fluid collections (5-20 mm diameter) in late diestrus (n = 4, mean day observed was 20.5 days postovulation, with a range of 18-24 days). Fecal samples collected at the time of ultrasou nd were evaluated via radioimmunoassay for progesterone metabolites, A substantial rise in fecal progestins was not identified until 7-9 day s postovulation. This study illustrates the value of combining the com plementary techniques of ultrasonographic ''mapping'' of events with f ecal hormone assay to enhance the accuracy of reproductive monitoring. (C) 1997 Wiley-Liss, Inc.