Reproduction in Domestic Animals

Captive Breeding of Cheetahs in South Africa 69ovulator (Wildt et al. 1980). Plasma progesterone concentrationsare now used routinely to confirm mating.The laparoscopic examinations supported the findingsof the oestrus observations as well as the hormonalpatterns (Fig. 4; Bertschinger et al. 1984).Induction of oestrusSome females that did not show spontaneous heatduring the breeding period were induced for naturalmating using a modification of the regimen described byHoward et al. (1992). Serum progesterone concentrationswere measured to ensure basal levels beforeinductions were attempted. On day 0, 200 IU eCG[Folligon, Intervet SA (Pty) Ltd, Isando, South Africa]was injected and followed by 100 IU hCG (Chorulon,Folligon, Intervet SA (Pty) Ltd., Isando, South Africa)72 h later. A male was introduced into the females’enclosures soon after the hCG-injection. Of the 11females treated 5 (46%) were mated and showed a rise inplasma progesterone. Four (36%) gave birth to livecubs. Progesterone concentrations remained basal in the6 (56%) unmated females.Heterozygosity of de Wildt cheetahs and heritability offemale fertility and cub mortalityThe de Wildt captive population had a mix of ancestryfrom Namibia and South Africa and had lower levels ofinbreeding than free-ranging cheetahs analysed(Wright’s Fst values – 0. 019 vs 0.13, respectively; SPSasidharan, unpublished data). These findings wouldseem to be logical, as in the wild, with very lowpopulation densities, the degree of inbreeding should begreater due to the restricted availability of potentialpartners. The heritability for litter size was high at0.5848 (SE 0.078) in the de Wildt pedigree (532 progeny,1975–2007; Sasidharan, unpublished data). The maternalheritability for cub mortality was estimated to be0.596 (SE 0.131). As in the wild (Caro 1994), cubsurvival was not affected by season.Male effectsBreeding agePotential breeding males were first examined at an ageof 3.5–4 years. The proportion of males found to haveacceptable semen quality (‘good’ and ‘fair’ categories)increased from 55.6% (n = 18) to 71.5% (n = 14) inthe age categories 3.5 to 4.5 to