Genetic polymorphism of milk protein in TNB cattle

Starch gel electrophoresis method was used to phenotype : casein and milk s erum proteins for 110 Turkish Native Black (TNB) cows. Frequencies were: al pha(s1)-casein A 0.000,alpha(s1)-casein B 0.925, alpha(s1)-casein C 0.075;b eta-casein A 0.840,beta-casein B 0.118,beta-casein C 0.042;beta-lactoglobul in A 0.234,beta-lactoglobulin B 0.766.beta-casein and beta-lactoglobulin lo ci were not in genetic equilibrium. However,the herd was in balance for alp ha(s1)-casein. The absence of genetic equilibrium for the 2 loci can be exp lained by chance as the herd was very small. The effect of migration and se lection except for natural selection were weak in this herd.