Expression of candidate genes of lipid metabolism in the Kazakhstani breeding simmental cattle

This research paper describes a gene polymorphism of growth hormone (GH), leptin (LEP) and diacylglycerol O-acyltransferase (DGAT) in Simmental cows of LLP “Galitskoe” of Pavlodar oblast. The frequency distribution of alleles and genotypes of the studied genes was held: at GH gene locus it was revealed that 19% of the 123 cows had VV genotype; 77% of the cows had VL genotype; 4% - LL genotype, at that the allele frequency was V - 58% and allele L - 42%.At Lep gene locus the genotype distribution was as follows: CC - 42%; CT - 48% and TT-10%. The frequency of allele C and T in the study was 66 and 34%. In DGAT gene locus genotype KK had 25%; genotype AA - 75%. The allelic frequency of K genotype was 63%, and A genotype - 37%.The study of GH gene expression showed that the minimum and maximum milk yield indicator of the test animals varied from 3089 to 8017 kg, the fat content ranged from 2.20 to 6.20%. Expression of Lep gene showed that the maximum milk yield was received from cows with CT genotype (9056 kg) and a minimum in the CC genotype (7407 kg), maximum fat content was observed in cows with CT genotype (6,1%), and the minimum in CC (2,2%) genotype. The variation of the studied milk yield indicators was from 2544 to 9056 kg of milk, fat content in the milk varied from 2.2 to 6.1%. According to DGAT gene milk production levels ranged from 3377 kg to 7985 kg of milk. The maximum yield of high fat content was obtained from cows with AK genotype (7985 kg - 5.9%), the minimum milk yield result was received from cows withKK genotype (3377 kg) and minimum fat cow result was received from cows with AK genotype (2.2%).