Genetic diversity of four Cameroonian indigenous cattle using microsatellite markers

Abstract

The genetic diversity of four indigenous Cameroonian cattle breeds was assessed using the Kenyan Boran breed as a reference breed. The Cameroonian cattle breeds were, Arab Shuwa, Ngaoundere Gudali, Namchi and White Fulani. A panel of 13 autosomal microsatellite loci was used. A total of 127 animals were genotyped, revealing 139 different alleles and 31 private alleles (21.3%). All the private alleles but two, allele 286 bp at ILSTS006 in the Arab Shuwa breed and allele 201 bp at ETH152 in the Ngaoundere Gudali- showed frequencies lower than 6 %. All the loci were polymorphic with a mean Polymorphic Information Content (PIC) of 0.75. Expected mean heterozygosity (Hex) ranged from 0.65-0.76. The mean observed heterozygosity (Ho) was higher in the Namchi. Only 6% of the total genetic variation could be attributed to the differences among the breeds. In all the populations, 80% of the overall loci do not deviate from the Hardy-Weinberg law. A high value of Number of effective migrants (Nem) (3.816) was found, combined to a low Fixation Index among individuals within populations (FST) (7%), which indicates high migration. No close genetic relationship was found between the Kenyan Boran cattle and the Cameroonian indigenous cattle breeds. This study demonstrates that the genetic diversity of Cameroonian indigenous cattle seems to have been affected by gene flow between breeds. Therefore, adopting effective breeding management practices will facilitate the conservation of those breeds and preserve their special characteristics.