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Abstract

The article highlights the issues of the adaptive response of the body of ewes to the influence of environmental conditions. Animals are related to three local breeds of meat productivity. Parameters of reproduction and growth rate of animals’ offspring were evaluated.
The research was conducted on sheep of meat breeds of different ecogenesis: Suffolk, Latvian Dark-Head, Dnieper Meaty, and crossbreds. The crossbred animals had clear genotypic and phenotypic differences, as well as conditions of housing in the facility – FOP “Gragdanova O.Yu” of Kharkiv region. Daily temperature fluctuations were taken into account during the two cycles of insemination of ewes and their reproductive capacity and growth rate of lambs obtained from 60-70 days.
It was found that ewes classified in the first group were inseminated at an average daytime temperature of 28.8 °C, which is almost 7 °C (%) higher, than animals in the second group. The difference between the compared groups was highly probable (p<0.001). Per 100 lambs, the yield of lambs in the first and second groups was 129.2% and 136.5%, respectively.
Significant fluctuations in the fertility of ewes and the intensity of growth of lambs from birth to 60-70 days of the age of different breeds and linear-breed combinations were revealed. High combining ability of breeders of the new line 024/063 of the Dnieper Meaty breed in terms of the fertility of ewes and intensity of growth of lambs at purebred breeding and crossing with the Latvian Dark-Head breed was revealed.

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