Application of DNA technologies in testing the TG5, SCD1, LEP genes of Holstin cows to increase the efficiency of milk production

The main and potential candidate genes associated with milk parameters can be considered alleles of thyroglobulin gene (TG5), stearoyl-coa-desaturase (SCD1) and leptin (LEP). For this purpose, a PCR-RFLP analysis of the polymorphism of the TG5, SCD1, LEP genes was carried out, DNA samples from blood leukocytes of Holstein cows, and the relationship of their polymorphic variants with economically useful traits was studied. Among them, 11 different complex genotypes were identified. Cows with the genotype combination TG5TCLEPCTSCDCC had the highest productivity in milk and fat - 8465 kg and 4,1 %, respectively. There were 1,4 % of such animals from the group studied.