No abstract

Cattle Breeding (accreditation certificate RA. RU.21PF59 of 12/02/15). Сhemical analysis was performed in the laboratory of ANO Center for Biotic Medicine, Moscow (accreditation certificate GSEN.RU.TSAO.311, registration number in the State Register ROSS RU. 0001.513118) Supported by Russian Scienсe Foundation

The improvement of breeding herds is based on the selection and intensive use in reproduction of linear sires with the desired genotype for DNA markers associated with the quality of meat products. The aim of our research was to study the formation of adipose tissue in Kazakh white-headed bull-calves from sires with different genotypes for the TG5 gene. The object of the study were bull-calves the offspring from sires with different genotypes for the thyroglobulin gene: TG5CC (n=6) and TG5CT (n=6). With the same live weight, young animals differed in weight and yield of internal raw fat with the superiority of progeny from heterozygous bulls by 1.8 kg (15.0%; P = 0.16) and 0.4% (P = 0.09). The TG5CT genotype in sires affected the better development of the subcutaneous fat in the middle of the last rib. The superiority of progeny from homozygous bulls was established by the back fat thickness at the root of the tail. Chemical analysis of slaughter products showed the advantage in fat synthesis of the offspring from sires with the TG5CC genotype. The intensity of fat deposition in sons from bulls with the TG5CC genotype is confirmed by the morphological composition of separate cuts. They exceeded their peers both in absolute mass and in proportion of adipose tissue in cuts. Under the same rearing conditions, the peculiarities in amount and distribution of adipose tissue in carcasses were determined in offspring from sires with different genotypes for the thyroglobulin gene.

Hematological studies were performed using standard techniques in the Laboratory of Agroecology of Nanomaterials and Test Center of All-Russian Research Institute of Beef Cattle Breeding (accreditation certificate RA. RU.21PF59 from 12/02/15). Analysis of chemical elements was performed in the laboratory of ANO Center for Biotic Medicine, Moscow (accreditation certificate GSEN.RU.TSAO.311, registration number in the State Register ROSS RU. 0001.513118).