Productivity, chemical composition and physical properties of wool under conditions of feeding ewes with increased levels of mineral elements

Increasing the productivity and quality of sheep products depends mainly on feeding, including providing the optimal amount of mineral substances, which significantly affect metabolic processes in the body. In this regard, there was conducted a study of the effect of increased levels, by 25 % of the existing norms, of a mixture of macro- and microelements (Sulfur, Zinc, Copper, Iodine, Selenium, and Cobalt) due to the additional introduction of sodium sulfate, zinc sulfate, copper carbonate, potassium iodide, sodium selenite, and cobalt sulfate to the diet of animals. The study was conducted on lactating ewes of the Prekos breed. The object of research was wool, samples of which were taken at the end of the experiment from the skin area behind the shoulder blade. It was established that the effect of mineral elements is aimed at intensifying the growth of wool, which is indicated by the increase in wool growth in the animals of the test group by 27.77 % compared to the control group (Р < 0.05). A tendency to decrease the number of beta- and increase in gamma keratosis was also noted, which is natural because gamma keratosis contains a large amount of sulfur-rich proteins. In contrast, beta keratosis contains a small amount of them. It was shown that the inclusion of increased levels of macro- and microelements, including Sulfur, in the essential diet leads to its probable increase in the wool of the test ewes (Р < 0.05) due to an increase in cystine (Р < 0.001). Tyrosine (Р < 0.05) and hexosamines (Р < 0.01) also increased significantly in the wool of animals in the tested group. The latter has a direct effect on the strength of the wool. The formation of wool fiber strength is also influenced by the growth of Sulfur and cystine, which directly form disulfide bonds. Thus, under the influence of the factors we applied, the breaking force of fibers was observed to increase by 15.25 % (Р < 0.05), from 7.41 сH/tex in the control group to 8.54 сH/tex in the test group. The alimentary factors we used had no significant effect on wool's total nitrogen content, tryptophan, and fineness.