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Biochemical-genetic variation was studied in springbok Antidorcas m. marsupialis (Zimmermann, 1780) from a large (N > 2000) "wild" population (n = 24) and a small (30 > N > 20) isolated farm population (n = 10) using electrophoretic allozyme analysis. Springbok showed polymorphisms at eight out of 46 loci. The springbok from the large population had a higher proportion of polymorphic loci (P = 15.6%) than those from the small population (P = 8.9%). Average heterozygosity (H = 5.1% and H = 4.1%, respectively) was similar for the two populations. This unexpected result is an artefact of the method for calculating H. H:P ratios are lower for the large population than the small one. The distribution of genotypes differed significantly from Hardy-Weinberg equilibrium for two loci. These were found to have a preponderance of homozygotes. This could not be explained by population fragmentation. The levels of polymorphism and heterozygosity are high compared to results from other African bovids.
For approximately 100 years blesbok - endemic to South Africa - have been extinct in the wild and confined to fenced game reserves or farms. Biochemical-genetic variation was studied in blesbok from five isolated populations using electrophoretic allozyme analysis. Body weights and liver mineral concentrations were also determined. Material was collected from three localities in the Orange Free State province: a large reserve (PRE, ca 10 000 ha, N = 500-600, n = 23); a smaller reserve (KOP, ca 3 000 ha, N = 150-200, n = 14) with animals derived from the same source; and a farm (MID, ca 4 000 ha, N = up to 700, n = 19). The other two localities were a farm in the northern Cape Province (BEN, ca 10 000 ha, N = 200, n = 18) and another in the southern Cape Province (BRA, ca 150 ha, N = 50-80, n = 27), both with populations derived from small founder stocks. Three loci were polymorphic: Pgm-1, Acy-1, and Gpi-1 but Acy-1 was the only one polymorphic in all five populations. Pgm-1 was polymorphic in two populations derived from the same source and Gpi-1 in the other from the Orange Free State. Calculated over 45 presumptive structural loci the mean proportion of polymorphic loci (P) was 3.5% (SD = 1.2%), and mean expected average heterozygosity (He) was 0.9% (SD = 0.25%). The populations separated out by genetic distance in two distinct groups, those from the Cape Province and those from the Orange Free State. There were considerable differences in mean body weight between some sites. No correlation could be detected with level of heterozygosity. Body weight appeared rather to be related to liver mineral levels. In particular the ratio between copper and molybdenium appears important with those animals high in copper and low in molybdenium having a higher body weight.
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