Microsatellite-based characterization of Southern African domestic pigs (<i>Sus scrofa domestica</i>)

Abstract

________________________________________________________________________________ AbstractThis paper details genetic characterization and trends from a microsatellite-based study of genetic diversity on southern African pig populations. A total of 351 pigs from three commercial breeds and three indigenous populations were genotyped at 39 loci. Differences among the levels of genetic diversity in populations correlated well with known population histories. In commercial breeds, heterozygosity was higher in the well established SA Landrace and Large White breeds (0.580 and 0.636) compared to the Duroc breed, established more recently (0.531). In indigenous populations, the highest heterozygosity levels were found in the Mozambican and South African populations (0.692 and 0.634) with a lower value of 0.531 in a smaller Namibian population. A hierarchical division of total genetic diversity revealed a high betweenpopulation component of 17.9%. F ST -and R ST -based analysis confirmed high levels of differentiation, with pair-wise comparisons between breeds indicating significant differentiation in 20 out of 21 comparisons.Results from an assignment test confirmed results from F ST and R ST and suggested a true genetic structure with significant differentiation between most populations sampled, but with little differentiation among the commercial SA Landrace and Large White breeds. The results are discussed with reference to known historical information on commercial and indigenous pig populations. This paper also presents new data on the optimization of microsatellite markers for application in Sus scrofa domestica.

Comprehensive Phylogenetic Reconstructions of African Swine Fever Virus: Proposal for a New Classification and Molecular Dating of the Virus

“…The assumption of pig introduction from Europe and the Far East was confirmed by phylogenetic analysis revealing contributions of both origins in the genetic pattern of local African pigs [69]. Following the circumnavigation of Africa by European nations during 15 th - 17 th centuries, pig breed types were introduced during 16 th and 17 th centuries [66], mainly by the Portuguese to the East Africa coast via Goa. Pig breeding diffused then slowly northward from Mozambique [68].…”

“…Domestic pigs have Eurasian and North African ancestral wild boar origins [64]. Even though Plug (2001) [65], claimed pigs were introduced in South Africa between the 3 rd and 7 th centuries, Swart (2010) [66] believes domestic pigs were not present in eastern and southern African livestock because of the nomadic lifestyle of pastoralists at this time. Domestic pigs may have been brought first by the Chinese around 600 years ago [67] then by the Portuguese 300 to 400 years ago [68], both during their exploration and conquest period for trade opportunities.…”

Some insights into the phenotypic and genetic diversity of indigenous pigs in southern Africa

“…An overall F ST value of 0.071 means that 92.9% of genetic variation was due to genetic variation within each population and 7.1 was between populations. Swart et al (2010) reported relatively little differentiation among field populations of pigs in Southern Africa (12.3% between Mozambican and Namibian pigs). Such findings indicate that the sampled pigs are strains within a breed that are spread across southern Africa.…”

“…Several articles have been published on indigenous pig production systems (Mashatise et al, 2005;Chikwanha et al, 2007;Chiduwa et al, 2008;Halimani et al, 2008) but these have been of limited scope and confined samples within districts. Other studies focused on disease and parasite tolerance (Haresnape et al, 1987;Zanga et al, 2003;Bastos et al, 2004;Penrith et al, 2004;Marufu et al, 2008), nutrition (Chikwanha et al, 2007), genetics and diversity (Ojeda et al, 2008;Ramírez et al, 2009;Swart et al, 2010). There are, however, several gaps in the literature on the genetic diversity, geographical distribution, physical attributes and production environments of indigenous pigs.…”

Comparative study on semen characteristics of Kolbroek and Large White boars following computer aided sperm analysis (CASA)

“…Indigenous pigs were long regarded as unsuitable for intensive commercial breeding because of their slow growth and inadequate meat production (Prolit, 2004). However, indigenous pigs exhibit well-established adaptations to severe environmental and management conditions (Swart et al, 2010). Moreover, there is lack of accurate method of predicting the fertility rate of Kolbroek boar sperm to determine their reproductive potential.…”