the present study is aimed at studying the growth and development of pure-bred bulls and heifers of the Aberdeen Angus breed by determining the live weight of young animals, average daily gain, growth coefficient and relative gain, as well as determining allelic variants of lipid metabolism and growth energy genes - leptin and thyroglobulin. Purpose: to study the growth rates of young Aberdeen Angus breed during the suc-kling period and the association of thyroglobulin and leptin gene polymorphisms with the growth rate of replacement young. It was found that all the studied livestock for the TG5 gene locus is in a state of genetic equilibrium, χ2 =0.2074 (P<0.01). Among the tested animals, individuals with the homozygous TGCC genotype were the most common – 35%. The expected frequency of occurrence of the rarest TGTT genotype was 0.67%, the growth rates of the animal were lower than their peers only at the birth stage of 23 kg and at 2 months they occupied an intermediate position with a weight of 71 kg. In subsequent periods, the calf grew faster than its peers with an increase in live weight by 0.8 - 4.7 and 2.8 kg. The number of animals with the preferred homozygous LEAA genotype is 15.5%. Starting from the age of two mon-ths, their live weight exceeded that of animals with a heterozygous genotype and a ho-mozygous genotype for allele B, by 4.6-5.8% at 2 months, by 5.9-8.3% at 3 months, by 5.2-9.9% in 4 months. and by 2.6-5.3% at 5 months of age, respectively.