Mitochondrial DNA diversity of Tanganyika Shorthorn Zebu cattle in Tanzania

Abstract

Indigenous cattle of sub-Saharan Africa exhibit high phenotypic variability, which in part is due to influence of environmental factors to which they have been exposed during their evolution. Analysis of genetic diversity at molecular level is essential for making informed decisions regarding choice of potential sub-populations for breeding and conservation. The objective of this study was to analyse genetic diversity of Tanganyika Shorthorn Zebu cattle in the Lake Victoria Basin area, which harbours a large indigenous cattle population in Tanzania. A total of 25 cattle of Sukuma and Tarime strains from Misungwi and Maswa Districts were genotyped by targeting 1200bp of mtDNA D-loop. Resulting sequences were used to estimate genetic diversity indices, analyse haplotype network and construct a Maximum-Likelihood Tree. Both sub- populations revealed high genetic diversity, with few individuals (8%) showing admixture between them. TheTarime strain tended toretain more genetic diversity than the Sukuma strain; and thus recommended as a target sub-population for selective breeding and genetic conservation of Tanganyika Shorthorn Zebu cattle in the Lake Victoria Basin of Tanzania. Further population genetics studies for indigenous cattle employing highly detective haplotype analysis tools are recommended in the area to clarify if the genetically divergent haplotypes observed could be a different sub-species or strain.