Influence of the allele spectrum of Gh/HaeIII gene on the growth and development of meat and wool sheep

Abstract

In this study the PCR-RFLP method was used to study the association of GH/HaeIII gene variations in Russian meat merino breed and Manych merino breed of sheep. Comparative analysis of the allelic spectrum of the GH/HaeIII growth hormone gene in sheep of the studied breeds was represented by the diff erent frequency of occurrence of two alleles – GHA, GHB and three genotypes – GHAA, GHBB, GHAB. The frequency of occurrence of the growth hormone gene desirable for selection of the allele GHB in a sample of sheep of the studied breeds varied from 0,25 to 0,46. The analysis of the results showed that the polymorphism of the GH/HaeIII gene in sheep of Manych merino breed was represented by a low frequency of occurrence of the allele GHB – 0,25, and a high allele GHA – 0,75. In sheep of Russian meat merino breed the frequency of occurrence of these alleles was relatively the same and amounted to 0,46 and 0,54. Thus, in sheep of Russian meat merino breed the frequency of occurrence of the selectively signifi cant allele GHB of the gene GH/HaeIII was 0,46. The presence of both GHA and GHB alleles caused the presence of desirable homozygous genotypes GHAA, GHBB and heterozygous genotype GHAB in the studied sample, which were distributed as follows 28,2; 19,6 and 52,2 %. Studies have shown that GH/HaeIII is polymorphic therefore the described genotypes for the gene GH can be useful for breeding programs of sheep Russian meat merino breed and Manych merino breed. Thus, the presence of the allele GHB in the genotype of sheep can have a positive effect on their meat productivity. Based on the identified polymorphism, information was obtained on the growth rate of replacement young sheep of Russian meat merino and Manych merino breeds from birth to 4 months of age.