PATTON, ML*; DEL CASTILLO, SM; BASHAW, MJ; J�CHLE, W; LAMBERSKI, N; BERCOVITCH, FB; Zoological Society of San Diego: Contraception in female giraffe with a GnRH analog (Deslorelin)

Giraffe (Giraffa camelopardalis) are sensitive to inbreeding. A significant increase in infant mortality occurs when closely related animals are paired. In captivity, separation of the sexes is not always possible necessitating the pursuit of reversible birth control. The most commonly employed method for giraffe contraception has been medroxyprogesterone acetate (MPA) injected at 6-week intervals. This method is labor intensive, and does not completely inhibit follicular activity. The objective of this study was to test a new contraceptive. Giraffe (n=2) were implanted with the GnRH analog, Deslorelin. One of these giraffe had been pretreated at 5-12 week intervals for 6 months with MPA. On the last MPA treatment day she was simultaneously implanted with Deslorelin. A second giraffe was injected with MPA 20 days post parturition and again 6 weeks later. Three weeks after, she was given the GnRH analog. Fecal samples were collected in order to measure sex steroids. Behaviors were recorded daily. Steroids in the first animal revealed evidence of ovarian activity throughout 6 months of MPA treatment. During this period she engaged in social behaviors more frequently than when she was treated with Deslorelin. Estrogens during MPA treatment were significantly higher than during treatment with Deslorelin, which could contribute to the increase in social behaviors. Breeding occurred 393 days post GnRH treatment. The contraceptive treatment affected the second giraffe differently. Although sex steroids remained at non-cyclic levels post parturition, she continued to exhibit breeding behavior. Deslorelin appears to be an effective alternative to MPA for birth control in giraffe. This GnRH analog successfully inhibited follicular activity for up to 500 days but was not consistently effective in preventing breeding behaviors.