AN ANALYSIS ON CYCLICITY AND PREGNANCY IN THE SOUTHERN WHITE RHINOCEROS (Ceratotherium simum simum) BY NONINVASIVE PROGESTERONE MONITORING USING VHF RADIO TELEMETRY

Abstract

Three female free-ranging white rhinoceroses in South Africa were monitored noninvasively and with the use of VHF radio telemetry by collecting fecal samples for progesterone metabolites measurement. All animals were immobilized so that radio transponders could be added in their horns. During this procedure blood samples were also collected. Blood assay results indicated pregnancy at the time of immobilization in two of the three rhinoceroses. Fecal samples were collected for a period of 90 days at about weekly intervals. Fecal sample collection from one rhinoceros failed, due to behavioural factors. Progesterone profiles of two rhinoceroses were created in this study. Concentrations above luteal phase values were found for both rhinoceroses during pregnancy. During the 50 days prior to parturition fecal progestagens declined, a feature so far only described in black rhinoceroses. Within 9-12 days post partum the progesterone concentration had reached follicular phase values. It was concluded that measurement of progestagens in feces with Enzyme Immunoassay (EIA) enables noninvasive monitoring of pregnancy (and presumably also cyclicity) in the southern white rhinoceros. Collectively the information generated in this study contributes to a better understanding of monitoring reproductive endocrinology in wild white rhinoceroses, information invaluable to the conservation and management of this species. This study also tried to emphasize the importance of further research on wild rhinoceroses to help the efforts to conserve this species on the long term.