Genetic Diversity and Population Structure of Zambian Indigenous Cattle

A study was conducted to determine the genetic diversity of Zambian indigenous cattle using microsatellites. In Zambia, cattle provide draft power, food, manure and generate income. DNA extraction followed the Qiagen protocol, and Arlequin V3.0 was used for data analysis. 72 unrelated animals from three regions, Eastern (Angoni), Southern (Tonga) and Western (Barotse), were sampled. 315 alleles observed were higher in TGLA 263 (106 bp) with 0.861, 0.824 and 0.753, BMS650 (160 bp) with 0.710 and SPS 115 (248 bp) with 0.581, 0.710 and 0.794 for Angoni, Tonga and Barotse, respectively. Effective allele frequency was 4.521 ± 0.351, 4.246 ± 0.299 and 3.888 ± 0.289 for Angoni, Tonga and Barotse, respectively. Global deficit of heterozygotes across populations (Fit) amounted to 4.2%. Overall mean deficit of heterozygotes (Fis = 1%), genetic differentiation among breeds (Fst = 3.2%),, and genetic flow between populations (Nm = 11.3) ranged from RM 067 (40.564) to BLI (3.016). Analysis of molecular variance revealed 2.7% genetic variation among populations and 97.3% within the cattle population, with a mean genetic diversity of 0.753. Structure analysis (PCoA) demonstrated the presence of two subpopulations in which all three populations are represented and these two groups showed evidence of substructuring. In the Bayesian analysis, Tonga and Barotse populations were clustered together, while the Angoni were separated from the rest of the populations in K = 2. There was no evidence of panmixia and linkage equilibrium; the VD (9.153) value is greater than L (5.929), indicating that the population was in equilibrium. This study presents a comprehensive genetic characterisation of indigenous cattle in Zambia, which is important for further studies.