The Dorper breed as a stage in the sustainable development of the agroindustry.

The economic condition, national economic significance and prospects for the development of sheep breeding in our country directly depend on the meat productivity of sheep. The purpose of our research was to study the qualitative indicators of sheepskins and the histological structure of the skin of Kalmyk fat-tailed rams and crossbreeds obtained on the basis of crossing of Kalmyk fat-tailed ewes with Dorper rams. The work was carried out in LLC "Agrofirma Aduchi", Republic of Kalmykia. It was found that the coarser wool of the rams of group I was 4.7 microns or 12.9%, in contrast to the peers of group II. The control animals have 40 quality wool, and the experimental ones - 36, that is, the wool of hybrid young animals is thinner by two whole qualities, which is a very good indicator for the textile industry. The fineness of the awn was thicker in purebred rams by 8.5%, the fineness of transitional hair and fluff by 17.8%, in contrast to hybrid young. In the study of the histological parameters of the skin, it was revealed that the rams of group I had 352.57 µm thicker skin (14.52%) in comparison with their peers in group II. In this case, the thickness of the layers of the total thickness of the skin in animals of group I is: epidermis - 0.8%, pilar - 69.8%, reticular - 29.4%; Group II - epidermis - 1.2%, pilar - 60.5%, reticular - 38.3%. The densest epidermis was found in crossbred young animals of group II. Their superiority in this indicator over their peers in the control group was 6.12 microns or 27.7%. This is due to the fact that in animals of the meat direction, the epidermal part (flesh) is thicker. Crossbred rams have a larger area of ​​sheepskins, the skin is more elastic, durable and less thick, such sheepskins are first-class raw materials for the industrial production of fur products. The density of the coat (the ratio of WF / PF) in crossbred rams is greater than that of purebred peers.

Correlative variation of economically valuable traits in South Kazakh Merino.

Fine-fleeced sheep are distinguished by numerous economically valuable traits that constitute the foundation for productive distinctions among breeds, populations, lines, and individuals. Many of these traits have already been mentioned or thoroughly examined during studies on the correlative variability of productivity indicators, blood parameters, characteristics of pulmonary gas exchange, histological structures of the skin, and features of the experimental sheep's coat. The objective of our research was to investigate the correlative variability of key economically valuable traits that characterize the overall functional state of sheep organisms under varying environmental conditions. The study was conducted at the "Sharbulak" breeding farms and the "Samat" peasant farms in the Kazygurt district of the Turkestan region. Our findings reveal that one-year-old rams surpass ewes in terms of live weight by 32-37% and in terms of unwashed wool shearing by 21-23%. Two-year-old rams outperform ewes in live weight by 2.15-2.17 times and in unwashed wool shearing by 2.38-2.44 times. The highest phenotypic variability in relative terms (as indicated by the coefficient of variation) is observed in the shearing of pure wool, with an average coefficient of variation of 18.1% across all sex and age groups of sheep. This is followed by the wool coefficient (17.4%) and the yield of pure fiber (12.5%). For each group of animals, the most substantial phenotypic correlation coefficients were observed between the live weight of sheep and the shearing of unwashed wool. On average, across all groups of sheep at the "Sharbulak" breeding farm, this phenotypic correlation reaches +0.411 ± 0.077. Correspondingly, for the sheep herd at the "Samat" peasant farm, it is +0.326 ± 0.075. The second-highest phenotypic correlation pertains to the cut of unwashed wool and the length of wool (with correlation coefficients of +0.156 ± 0.058 and +0.145 ± 0.057, respectively, for the herds). The third-highest correlation involves live weight and wool length (+0.131 ± 0.085 and +0.105 ± 0.078, respectively). No statistically significant differences were identified in the average correlation coefficients between the live weight of sheep, the shearing of unwashed wool, and the length of the staple among the flocks of sheep at the "Sharbulak" breeding farm and the "Samat" peasant farm.