The completeness of animal nutrition rations in terms of the content of minerals is considered one of the conditions for balanced feeding, since their lack in the diet often leads to metabolic process disorder among animals, which reduces growth and development, productivity, disturbs reproductive ability, and develops endemic diseases. Currently, for the partial compensation of trace mineral deficiency in the diets of use mineral substances of natural origin. One of such sources is bentonite clay of the Zamankul deposit. Taking into account the significant increase of the economically useful traits among young cattle identified in our studies when feeding with bentonite, substantiated by physiological studies, we performed research to study the exchange of nitrogen, mineral elements and the digestibility of nutrients in the body of 9 - 18-month-old cattle of the Simmental breed for fattening at the farm “Kaloev”, stanitsa Zmeyskaya, North Ossetia-Alania. Studies have established the digestibility of nutrient increase in the feed ration from 1.8 to 3.5%, a significantly greater retention of nitrogenous substances in the body of animals fed with bentonite - by 8.2%, a significant improvement of mineral element use in the feed.

We studied the effect of putrefactive decomposition of sheep hooves on the cellular composition, physical and chemical properties of blood, as well as on the biochemical composition of its serum. In the production conditions of the sheep-breeding complex, orthopedic medical examination and identification of sheep with putrefactive decay of the hooves were carried out. Subsequently, blood samples were collected from 10 sick sheep and 10 clinically healthy animals for general clinical analysis and biochemical analysis of their serum. The selected blood samples were analyzed on the haematological automatic analyser "Abacus vet 10" and the semi-automatic biochemical analyser "Stat fax 300". In the biochemical composition of blood serum, putrefactive decay of hooves increased the concentration of total protein by 7.94%, total bilirubin by 22.08%, urea by 75.18%, and reduced the concentration of glucose by 17.88% relative to clinically healthy sheep. At the same time, the activity of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and creatine kinase in the blood serum of sheep with putrefactive hoof decay exceeded similar indicators in clinically healthy sheep by 9.65%, 9.16%, 13.70%, and 19.90%, respectively. In addition, the concentration of sodium, potassium, calcium, phosphorus and magnesium in the blood serum of sheep with putrefactive decay of hooves was by 15.44%, 9.64%, 3.49%, 25.35% and 9.78% less than in the blood serum of clinically healthy sheep.

Sheep breeding is currently an intensively developing branch of animal husbandry. However, one of the limiting factors of its further economically viable development is the mass distribution in the conditions of large sheep-breeding farms with a non-walking technology for keeping purulent-necrotic and putrefactive lesions in the tissues of the distal part of the limbs. The etiology and pathogenesis of these pathologies is currently not fully scientifically substantiated and detailed. In this regard, we assessed the effect of putrefactive decay of the hoof horn in sheep on its biochemical and biomechanical properties, as well as on hemodynamics in diseased animals in comparison with clinically healthy ones. According to the results of the studies, it was determined that during the putrefactive decay of the hoof horn, the percentage of moisture was higher by 12.37%, and the inorganic residue (ash), fat, protein and sulfur was lower by 73.84%, 36.84%, 5.92 % and 3.82% than in its normal morpho-functional state, respectively. This, in turn, had an impact on the biomechanical properties of the hoof horn, namely, during its putrefactive decay, a decrease in compressive elasticity by 3.82%, tensile strength by 28.76%, resistance to repeated bending by 9.61% was recorded relative to similar biomechanical indicators in samples of the hoof horn obtained from clinically healthy sheep. At the same time, in the hemodynamics of diseased animals with putrefactive decay of the hoof cover, in a comparative aspect with similar hematological indicators in clinically healthy sheep, a decrease in the number of erythrocytes and platelets by 28.94% and 7.03%, a decrease in hemoglobin concentration and hematocrit value by 22.88 % and 8.80%, an increase in the number of leukocytes and erythrocyte sedimentation rate by 89.14% and 44.70%, respectively.

It is difficult to objectively assess the functional state of the endocrine gland based on the level of hormones in the blood, since hormones vary significantly in absolute values during the day. Therefore, to assess the functional state of the endocrine glands in biological and medical practice, "load" is used. The criterion for evaluating the state of the gland is the change in the concentration of secreted hormone by the endocrine gland in response to the stimulation. As is known, the testis reacts relatively quickly to stimulation with chorionic gonadotropin. This allows us to determine the limiting features of the hormone-synthesizing and hormone activity of the testes and determine the maximum response of the testes to this stimulation. The object of the study was 6-month-old boars of large white breed, Landrace and tempo, 10 heads from each breed. In order to determine the functional endocrine reserves of the testes at 6 months of age, CG (chorionic gonadotropin) was administered intramuscularly at a dose of 1000 IU. HCG was administered 3 times every 72 hours. Blood for the determination of testosterone was taken before administration of HCG and 2.12,24,48 and 72 hours after its administration. Testosteron was determined by the enzyme immunoassay. Sperm counts in 18-month-old boars were studied using standard methods. Performed three-fold loads with an interval of 72 hours showed that the hormone level increased to 7.2±0.6 nmol/l in a large white breed 72 hours after the first administration of HCG, in the Landrace breed to 7.9±0.5 nmol/l, in the Duroc breed to 7.0±0.7 nmol/l, in the tempo breed to 7.0±0.6 nmol/l. After the second injection HCG the testosterone levels in large white breed boars increased by 1.2 nmol/l, and breeds Duroc 1.7 nmol/l, Landrace 0.1 nmol/L. In the boar breed, tempo increased the hormone by 0.4 nmol/l. In this regard, the increase in testosterone in experimental boars continued, which means that the reserves of endocrine function of the testes were not fully realized, so the 3rd stimulation of HCG was also performed. In a large white breed of boars and Duroc, the maximum concentration of testosterone was observed 24 hours after administration of HCG and was 9.2±0.7 and 8.9±0.5 nmol/l respectively. In the Landrace and tempo breeds, the maximum concentration of testosterone was 2 hours after 3 CG stimulation and was 8.2±0.6 and 7.5±0.6 nmol/l. respectively. In terms of sperm, its fertilizing capacity and the production of live piglets per Farrow, the indicators were higher for boars of large white breed and Duroc.