Proceedings of the World Congress on Genetics Applied to Livestock Production, 11.550 Genetic variability and relationships among nine southern African and exotic cattle breeds L. van der Westhuizen 1,2 , M.D. MacNeil 1,2,3 , M.M. Scholtz 1,2 & F.W.C. Neser 2 1 ARC-Animal Production Institute, Private Bag X2, 0062, Irene, South Africa PienaarL@arc.agric.za (Corresponding Author) 2 Department of Animal, Wildlife and Grassland Sciences, UFS, P.O. Box 339, Bloemfontein, 9300, South Africa 3 Delta G, 145 Ice Cave Road, MT 59301, Miles City, USA Summary An existing 11 microsatellite marker database that resulted from parentage verification in response to requests from industry, was used to assess genetic diversity among nine breeds of cattle. These breeds were drawn from B. indicus (Boran (BOR) and Brahman (BRA)), B. taurus (Angus (ANG) and Simmental (SIM)), and B. taurus africanus (Afrikaner (AFR), Bonsmara (BON), Drakensberger (DRA), Nguni (NGU), and Tuli (TUL)). Due to the cost of genotyping, genetic diversity studies using SNPs rely on relatively low numbers of animals to represent each of the breeds. Large numbers of animals have been genotyped for parentage verification using microsatellite markers, therefore, the microsatellite information on large numbers of animals has the potential to provide more accurate estimates of genomic diversity. A minimum of 300 animals were randomly chosen from each breed and were used to assess within- and between breed genetic diversity. All breeds had high levels of heterozygosity and minimal inbreeding. There were distinct differences among the three groups of cattle, but also support for the notion of taurine influence in some of the Sanga and Sanga-derived breeds. There is a notable similarity of results observed here using a limited number of genetic markers and large numbers of animals with the results of studies with similar objectives which used substantial greater numbers of markers but much fewer animals. Keywords: cattle, genetic diversity, Sanga, Southern Africa Introduction Genetic drift due to small effective population sizes and founder effects, and natural and artificial selection have caused the development of distinct breeds (MacHugh, 1996). Breeds of Africa include the indigenous livestock cattle breeds of southern Africa that are Sanga (African hump-less Bos taurus x humped Bos indicus) and Sanga derived cattle. Sanga cattle, especially those that are indigenous to southern Africa, have cervico-thoracic humps and classified as Bos taurus africanus (Meyer, 1984). These breeds include the Afrikaner, Nguni, Drakensberger, and Tuli; as well as Sanga derived composite breeds such as the Bonsmara. They are well adapted to the harsh climatic and other environmental conditions encountered under extensive ranching in South Africa (Schoeman, 1989). However, they are relatively poorly characterized at the genomic level in comparison to many taurine and indicine breeds. Using genotypes at microsatellite loci, Greyling et al. (2008), Pienaar (2014), and Sanarana et al. (2015) characterized individual populations of Bonsmara, Afrikaner, and