Genetic control and adaptive significance of blood potassium types in some indigenous and exotic breeds of sheep in India

Abstract

On the basis of concentration of potassium in the blood, sheep can be classified into two distinct groups—high (HK) and low (LK). The two types have been observed to occur in all the seven indigenous breeds whereas only one type (LK) was noticed, in exotic breeds. There are distinct breed differences in the proportion of these types and concentration of potassium. The blood types are controlled by a single locus, KL being dominant over KH. There is evidence that KL is partially dominant. Exotic LK sheep are homozygous whereas indigenous LK are both heteroygous and homozygous. Natural selection is not operating against one of the types.