*Department of Biological Sciences, University of Malawi, Chancellor College, P.O., Zomba, Malawi
**NEPAD African Biosciences Initiative, Policy Alignment and Programme Development Directorate, NEPAD Agency, c/o CSIR Building 10F, Meiring Naude Road, Brummeria, Pretoria, Republic of South Africa
Online published on 13 February, 2014.
Genetic variation has enabled selection and improvement of crop varieties and livestock breeds. In this study, the genetic variation between and within nine dairy cattle breeds was investigated at six microsatellite loci. Allelic size variation was generally high across the populations with a total of 55 alleles scored. Shannon Information Index (I) and Effective number of alleles (ne) showed that Mbala population was the least diverse (I=0.71; ne=1.9) and Mikolongwe population was the most diverse (I=1.21; ne=2.92). Only 22% of the population-locus combinations deviated from Hardy-Weinberg proportions probably due to Wahlund effect evidenced by 56% homozygosity excess observed among the populations. The populations were significantly differentiated at 95% CI with a high FST value of 15% which was supported by low gene flow (Nm=1.13). Cluster analysis showed that the Jersey population at Chikunda has not been greatly introgressed by Friesian alleles. Precise breeding plans and goals are required in order to control inadvertent mixing of breeds which can threaten the conservation of genetic variation within and between breeds.
Dairy cattle, microsatellites, Friesian populations, Jersey populations, DNA, Genetic variation
