GENETIC POLYMORPHISM OF BLOOD POTASSIUM IN GOATS BELONGING TO THE CARPATHIAN BREED

Gh. Hrincă

Abstract
In the goats belonging to the Carpathian breed the genetic polymorphism at the determinant locus of blood potassium was revealed by the flame photometry method. The kalemic system in the Carpathian breed is characterized by a polymorphism of middle level due to the existence of the two phenotypes and of the three genotypes. The polymorphic character of this system is given by the distributional discontinuity of potassium ions in whole blood, the discontinuous space ranging between 16 mEq/l and 21 mEq/l. The animals with potassium ion concentration below the discontinuity space are of LK type, and those with ionic concentration above the discontinuity space are of HK type. The blood potassium level is determined by two alleles, K^L and K^h, being in incomplete dominance relationship; the allele K^L, responsible for low potassemia, is dominant compared to its recessive K^h allele which causes high levels of blood potassium. These two alleles at the Ks locus, located on an autosomal chromosome, determine three genotypes: K^LK^L (dominant homozygote), K^LK^h (heterozygote) and K^hK^h (recessive homozygote). In the Carpathian breed the allele K^h is more frequent (89.79%) than its dominant K^L (10.21%). The phenotype HK (80.62%) achieved a much higher frequency than the phenotype LK (19.38%). The recessive homozygotes recorded a high frequency (80.62%), the incidence of heterozygote's was moderate (18.34%), and the dominant homozygote were found sporadically in population. Consequently, the summed homozygosis for both types (81.66%) was much more present than heterozygosis (18.34%).

Key words: blood potassium, genetic polymorphism, goat