Genetic polymorphism of milk protein in TNB cattle

Starch gel electrophoresis method was used to phenotype : casein and milk serum proteins for 110 Turkish Native Black (TNB) cows. Frequencies were: αs1-casein A 0.000,αs1-casein B 0.925, αs1-casein C 0.075;β-casein A 0.840,β-casein B 0.118,β-casein C 0.042;β- lactoglobulin A 0.234,β-lactoglobulin B 0.766.β-casein and β-lactoglobulin loci were not in genetic equilibrium. However, the herd was in balance for αs1-casein. The absence of genetic equilibrium for the 2 loci can be explained by chance as the herd was very small. The effect of migration and selection except for natural selection were weak in this herd.