An IRF/ SOS Rhino sponsored integrated approach to enhance the reproductive performance of white rhinoceroses in the EEP

1. The combination of endocrine monitoring with ultrasonographic examinations of the entire female reproductive tracts under anesthesia provided information which neither of these techniques on its own would have been able to supply.
2. The combination of Detomidine, Buthorphanol, followed by Ethorphine and i.v. Ketamine proved to be a reliable anesthesia protocol for white rhinoceroses.
3. Semen collection by electroejaculation proved to be a reliable technique: ejaculates gathered by this method were used for cryopreservation and results suggest that post thaw quality is sufficient for artificial insemination.
4. In addition to female related infertility, infertile or subfertile males with inadequate ejaculate quality are a major cause of the low reproductive performance in captive white rhino.
5. Acyclicity is a major cause of infertility in female white rhinoceroses. Acyclic females consist of two groups, a) females with no luteal activity (flatliners) and b) females with persistent luteal activity. Ultrasound examinations revealed several causes for flatliners; in adult females the causes are either small ovarian cysts, 'micro corpora lutea' or inactive and small ovaries. In contrast to the small ovarian cysts in 'flatliners', females with persistent luteal activity had cysts of up to 10 cm in diameter; the permanent estrogenic state of these large cysts cause severe uterine pathologies resulting in infertility.
6. Uterine pathologies were identified in about 55% of the females investigated; about half. of these animals (27.5 %) were classified post reproductive due to severity of pathologies, whereas the other 27.5 % were still considered to be fertile beside mild pathologies were present. Females which do not bred before the age of 12 - l5 y, are likely to develop uterine pathologies. In contrast these pathologies were not seen in old (>25 y) proven breeders.
7. A reliable technique for artificial insemination and for the intra-uterine placement of sperm is available.