Inheritance of breeding traits in Karakul sheep under different selection approaches.

In the previous century, each intrabreed type of the Karakul sheep breed was characterized by significant numbers, representing a super population with rich genetic diversity. However, over time, the genetic diversity within the breed's gene pool has undergone significant depletion. At present, the Karakul breed is predominantly composed of only two small populations, distinguished by their fur colors: black and gray. Consequently, under such circumstances, genetic advancements in breeding endeavors are likely to be relatively limited, especially given the potential risk of these populations disappearing altogether in the future. Hence, the preservation and judicious utilization of the available genetic resources within the black and gray Karakul sheep populations hold paramount importance in breeding efforts. The primary objective of our research was to investigate the heritability of breeding traits among gray lambs through various selection options. The study was conducted at the "Kumkent" base farm in the Sozak district of the Kyzylorda region. Our findings revealed that the inheritance of gray and black fur colors across the different selection options occurred in a consistent ratio. In the first selection variant (a gray ram with even silver marking ♂ x a black jacket fur type ewe with intense pigmentation ♀), the proportion of gray offspring was 50.6%. Similarly, in the second selection variant (a black jacket fur type ram with intense pigmentation ♂ x a gray ewe with even silver marking ♀), the proportion of gray offspring was 49.6%. The percentage of black lambs obtained in both selection options was nearly equivalent, with 49.4% and 50.4% in the first and second variants, respectively.

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.

Increasing the meat productivity of young sheep based on the use of the gene pool of the Dorper and Hissar breeds.

In the pursuit of enhanced mutton production, improving the genetic reservoir of sheep with early maturation and high meat productivity is imperative. This study aims to assess the efficacy of integrating Dorper and Hissar rams into the breeding program of Kazakh fat-tailed coarse-haired ewes for generating young mutton. The research involved forming three groups, each comprising 40 ewes of the Kazakh fat-tailed coarse-haired breed, based on analog pairs. Ewes in Group I were inseminated with Dorper ram semen, those in Group II were inseminated with Hissar ram semen, and Group III served as a control with purebred Kazakh fat-tailed coarse-haired sheep breeding. Results revealed that crossbred rams in Group II achieved a significantly higher live weight of 45.2 kg at 120 days of age, surpassing the other groups by 9.7 kg and 10.6 kg. Crossbred gimmers in Group II reached a live weight of 42.0 kg by 4 months, outpacing the other groups by 12.2 kg. The crossbred lambs exhibited an expansive, deep, and sturdy physique, indicative of elevated meat productivity. Physique index analysis displayed that crossbred rams exhibited elongated limbs, bulkiness, and massiveness compared to purebred Kazakh fat-tailed coarse-haired lambs. In the 4.0-4.5-month age range, crossbred rams demonstrated a higher carcass muscle yield than their purebred counterparts, albeit the latter exhibited a 0.18% greater bone yield. Moreover, the meat of groups I and II sheep contained 19.6% and 20.1% protein content, respectively, surpassing the local Kazakh fat-tailed sheep population by 0.7% and 1.2% in absolute terms.