Purpose: to evaluate the biological properties of growth hormones (GH, IGF-1) in the dairy and vegetable periods of growing Holsteinized Black-and-White heifers, determined by their ability to regulate the age-related variability of the leukocyte composition of the blood.

Materials and methods. The work was carried out in the conditions of the SPK «Koelginskoe» named after V. I. Shundeeva I. N. (Chelyabinsk region) in 2019–2020 on heifers of Holsteinized Black-and-White breed during the dairy and vegetable growing periods. Animals up to 3 months of age were kept individually, and then in groups of 10 animals. Milk and milk replacer were used in the diet of animals only up to 3 months, and then they were transferred to a plant-based diet. When compiling the feeding ration on the farm, they were guided by the norms of the VIZh. The experimental group (n=10) was formed according to the principle of approximate analogues, heifers were included in its composition after a clinical examination, which was carried out later with each blood sampling. For laboratory studies, whole blood and blood serum were used. Blood sampling was performed at 1, 3, 6, 9, 12 and 13 months of age in the morning before feeding. The leukocyte composition of the blood, the concentration of growth hormone and IGF-1 were determined.

Results. It was found that the total number of leukocytes in the bloodstream of heifers increases with age by 28.06% (p<0.05), which is accompanied by an increase in the percentage of eosinophils, segmented neutrophils and monocytes in the leukogram by 45.31; 5.70 and 50.00% (p< 0.05), a decrease in lymphocytes, rodshaped neutrophils by 5.69 and 43.39% (p<0.05). The level of STH by the end of the heifer rearing period decreases by 54.32% (p <0.05), and the insulin-like growth factor type 1, on the contrary, increases by 32 times (p<0.05). The values of the correlation coefficients in the statistical matrix of STG and IGF.

Purpose. to study the influence of the feeding scheme of the feed additive «Yeast hydrolyzate “Protamine”» on the activity of microbicidal mechanisms of blood neutrophils in pigs.

Materials and methods. In the conditions of the Baikovo pig farm in the Bryansk region, 3 groups of 10 piglets of 58-61 days of age (on growing) with a live weight of 11.16 ± 0.01 kg were formed from sows (large white x Landrace), inseminated with Duroc boar sperm. Animals of group 1 were control, piglets of group 2 received 5 grams of feed supplement «Yeast hydrolyzate “Protamin”» with water once a day for 75 days according to the scheme: 7 days — watering, 7 days — break; animals of the 3rd group also received once a day with water 5 grams of feed additive «Yeast hydrolyzate “Protamin“» for 75 days, but according to the scheme: 7 days — drinking, 14 days — a break. Blood for the study was taken from 5 animals of each group from the jugular vein in the morning before feeding before the start of the experiment, after 35 and 75 days, and also one month after the end of drinking the drug. One month before the 1st blood sampling, all piglets were vaccinated against classical swine fever. One month before the 2nd blood sampling, all piglets were vaccinated against swine erysipelas, and the day before this blood sampling, they were revaccinated against classical swine fever. One month before 3 blood sampling, all pigs were revaccinated against swine erysipelas. A month after the end of the feeding of the feed additive to the experimental animals, pigs of all groups were subjected to technological stress — they began to prepare for slaughter: they began to starve, carried out a veterinary examination and weighing, after which they took blood for analysis. It was found that post-vaccination stress caused a more pronounced decrease in oxygen-dependent and oxygen-independent microbicidal activity of blood neutrophils than pre-slaughter stress.

Results. The use of the feed additive «Protamin» according to both schemes contributed to an increase in oxygen-independent microbicidal activity and the appearance of an adaptation reserve of oxygen-dependent microbicidal activity, which is more pronounced in pigs when using the drug according to the scheme: 7 days — drinking, 7 days — a break. The absence of stressful influences led to the optimization of homeostasis.

Purpose of research was to study the effect of enzyme supplements and humic substances on the histostructure of the glandular part of the stomach of broiler chickens.

Materials and methods. The experiment lasted 49 days. In the first 4 weeks, the level of metabolic energy in the diet was 10 kcal per 100 g of feed below the recommended level, then until the end of the experiment it was 5 kcal lower. Group 1 received the main diet, balanced in all respects. Group 2 received the enzyme preparation «Kemzaym» 1 g/kg feed. It contained beta-gluconase, cellulase, pentosanase, protease, lipase and alpha-amylase. Group 3 received sodium humate 1 g/kg of feed. Group 4 received both «Kemzyme» (1 g/kg) and sodium humate (1 g/kg) at the same time. Slaughter of chickens was at 28 days and 49 days of age. Samples of the glandular part of the stomach were taken from 5 chickens from the group.

Results. The study of the histological picture showed that up to 49 days of age, the development and formation of the structures of the wall of the glandular stomach occurs. This is expressed in an increase in the thickness of the organ wall, mainly due to the submucosal layer. The use of «Kemzaym» continuously during the entire cultivation leads to a decrease in the thickness of the entire wall of the organ and inhibition of the development of the submucosa. There is also an irritating effect of the drug on the mucous membrane. In the first period, this is expressed in a decrease in the height of the mucosa, foci of violation of the integrity of the epithelium, atrophy of the glands of the mucosa and lymphocytic infiltration of the lamina propria are observed. In the second period, this is expressed in an increase in the thickness of the mucosa in the absence of destructive changes in its histological picture. Such a reaction of the structures can be considered as an adaptation of the stomach wall. The use of sodium humate in the first period leads to an increase in the thickness of the submucosa. No negative effect on the structures of the mucosa was found during this period. In the second period, this additive causes a decrease in the thickness of the submucosa. During this period, an increase in the layer of the mucous membrane is observed without destructive changes in its structure. The combined use of sodium humate and the enzyme complex does not have a positive effect on the wall of the glandular stomach.

Conclusion. Studies have shown that long-term continuous use of enzyme supplements leads to a decrease in the production of the stomach's own enzymes. The use of sodium humate has a positive effect only in the first period, which indicates that the body is getting used to this additive.

Purposes: to study the daily rhythms of the heart rate in 20 healthy Doberman dogs; obtaining reference values of time indicators of heart rate variability; study and determination of the type, identification of the predominance of the electrocardiological syndrome in this group of animals.

Materials and methods. Due to the high prevalence of the disease: dilated cardiomyopathy (DCM) in Dobermans and a high risk of sudden death associated with the development of ventricular tachycardia, we conducted a study of heart rate variability in 20 clinically healthy Doberman dogs in order to study the electrical activity of the heart, heart rate variability, identify reference values of HRVi  parameters, to study and determine the prevalence of which electrocardiological syndrome in this group of animals. The study of circadian rhythm was carried out using 24-hour Holter ECG monitoring on an outpatient basis.

Results. When analyzing the daily fluctuations of the intervalogram for every 2 hours, it was found that the maximum heart rate of 90 beats/min is in the range of 16:00–18:00, the minimum is 71 beats/min in the range of 4:00–6:00. Received temporal parameters of heart rate variability. It was registered that the parameters responsible for the general autonomic tone (SDNN, SDANN, HRVi) are higher during the daytime. Parameters indicating high frequency variation and tone of the parasympathetic nervous system (SDNN, rMSSD, SDSD) are higher at night. The predominance of normocardial syndrome in Doberman breed dogs was established during the assessment of the daily intervalogram.

Materials and methods. The research materials included the skin samples taken from purebred Poltava Meat Breed boars of the main herd and from adult male wild boars. The epidermal barrier variability in the skin of wild and domestic boars was studied by comparing the structural and functional parameters in similar topographic areas of the animal bodies, with similar natural and climatic conditions (such as: the season of the year, the animals’ habitation area). On stained skin sections, the thickness of the stratum corneum (i.e. the outer epidermis layer) and the thickness of the epidermis layers underlying stratum corneum (i.e. the inner underlying layers), the length of the epidermis projections in tenfold repetition were determined. Based on the primary data, the total thickness of the epidermis and the ratio of the outer and inner epidermis layers were calculated, folding of the epidermis. All the results obtained were processed by statistical methods.

Results. Poltava Meat Breed boars have a number of structural and functional features associated with the performance of protective functions by the skin epidermis. These features, most of which are related to the stratum corneum layer, reliably differ from those in the wild boars. We found that the stratum corneum thickness (by 11.89 microns (p≤0.001) or 32.91%), the relative thickness of the stratum corneum in relation to the thickness of the epidermis (by 12.96% (p≤0.001), the ratio of the stratum corneum and the inner (underlying) layers (by 0.415 or 41.29% (p≤0.001)), are lower in domestic boars. The variability of the thickness ratios of the stratum corneum with the epidermis and the inner underlying layers was higher in the group of domestic boars. The thickness of the underlying epidermis layers did not differ significantly in thickness, regarding the studied groups of pigs. The morphological difference between the inner (underlying the stratum corneum) epidermis layers of the Poltava Meat Breed boars, and those of the wild boars, is the presence of more intense basophilia and clearly visible nuclei of keratinocytes. The performed correlation analysis showed the presence of a greater number of reliable correlations between the indicators in the group of Poltava Meat Breed boars.

The goal is to assess the influence of platelet autoplasm on healing damaged tendons in rabbits.

Materials and methods. The study on the effect of platelet autoplasma on the regeneration of damaged tendon fabric was carried out on rabbits.

In the experiment, rabbits were applied in the field of Achille tendons, since this tendon in animals is injured quite often [1]. Then in the area of ​​damage to the tendon, the experimental group of rabbits was administered tap, while the injured tendons of rabbits of the control group were left without treatment. An intradermal seam was imposed on wounds in the field of leather. A month later, animals of experimental and control groups took samples of tendon fabric in places of damage to immunohistochemical research using the Ki-67 marker, which made it possible to visually demonstrate the action of platelet autoplasm for the regeneration of damaged tendons.

Results. The Ki-67 proliferation marker made it possible to clearly reveal the effect of tap on regeneration during damage to the tendon fabric in rabbits. In damaged tendon tissues in rabbits, proliferative processes go more active than in a healthy tendon. Thanks to the studies carried out, it was established that TAP stimulates proliferative processes in tendon tissues. The proliferation index is higher in the tendon tissues of the experimental group of rabbits, which was administered by TAP than in the control group and in a healthy tendon fabric.

Mastitis is one of the most common diseases of dairy cattle that appreciates the enormous losses of farm worldwide. Current treatment and prevention developed at the moment does not guarantee the reliable protection of animals from the disease, given the polyethological nature of mastitis. An important method of combating this problem may be a selection aimed at improving the immunity of livestock to the inflammation of the breast.
The purpose of the article was to search and systematize information on genes associated with the sustainability of dairy cattle towards the development of clinical mastitis and SCS in milk, mainly among the Holstein breed. Also, the publication presents data on the genomic assessment of the bull leader 395, obtained on the basis of St. Petersburg University of Veterinary Medicine, in terms of indicators related to the sustainability of the offspring to the Master.
The relationship between the markers of high milk productivity and is low-resistant to the mastel, the protein composition of milk and the frequency of the inflammatory processes of udder. The general mechanisms for the formation of immunity, nonspecific resistance and stability to the mastel are illustrated. A correlation is indicated between allele variants of genes regulating cell cycle or modulating autoimmune processes, and the SCS level in milk. When implementing a genomic estimate of the bull, the leader 395 was identified by its potential as an improved indicators such as SCS, mastotustability, the form of udder, the fatness of milk in daughters.

The purpose of the research was to analyze the results of a change in service period, yaliiness and reduction of losses using the new protocol for the prevention of gynecological diseases, as well as the mathematical calculation of the forecast of changes in the coefficient of life-lifetime reproduction of cows.
Materials and methods. The work was performed on 215 cows of the Holstetskaya breed of Leningrad type. To prevent the occurrence of gynecological diseases and the afternoon complications, we have been tested by the previously developed preparation of the new generation "Aldecosptimol". It is a preparation of a wide range of action, not a hormonal agent and non-antibiotic groups. As part of the conducted studies, it was found that the minimum bactericidal concentration of the drug is 0.001% of the working solution, which makes it possible to use it on the mucous membranes of the organism of animals and develop on its basis a new protocol for the prevention and correction of various deviations that increase the effectiveness of the insemination and the level of reproduction. Considering the activity of the drug Aldecosptimol and its bactericidal action, we investigated the possibility of its use to prevent postpartum gynecological complications. The following drugs were included in the composition: aldisseptimol, non-α-f2, nitamin. As a control, the drug was used non-aoxyl, well-proven himself for everyday work in veterinary practice. Studies were conducted within 4 months at the first switches of the Holstein breed.
Results. The Aldecosptimol preparation in the new protocol has positively influenced the process of subbatencation, the active restoration of the epithelial fabric of the uterine structure and the proliferative process in the uterus, reduced the arrival time in the first hunt and increased the effectiveness of artificial insemination. Thus, the use of a new protocol for the prevention of gynecological diseases made it possible to reduce the service period from 179.9 days (control) to 102.3 days (experience). Calculation of the effectiveness of the application of the new protocol revealed an increase in reproduction by 7.2% (chicks) or 14.4% to exit calves. 

Purpose: development of a new way to obtain a drug of natural genital pheromones of boar, and its approbation in production conditions.
Materials and methods. A method of manufacturing a drug of natural genital phargs, including grinding of testicles, obtained from half-arms, incubated homogenizates at a temperature of 37-39 ° C for 50-60 min, adding inkubat urine of semi-cream boars and distillation of the mixture in the rotary evaporator R-213B to the urine incubate. The finished preparation was a transparent liquid of a yellowish shade with a specific smell. Checking the drug on pigs showed its harmlessness, clinical parameters and general hematological indicators in animals after treatment with the drug were within physiological boundaries.
Results. In the scientific and production experiment, it was established that after stimulation of 5-month-old impaired repair pigs with a preparation in a dose of 0.5 ml / goal twice a day, sexual ripening has occurred at a 178-day age, which was 6 days before compared to Pilts stimulated by a synthetic analogue of the Formon Sidor (Germany's production) and 14 days earlier than in the pigs of the control group. It was found that pigs treated with the preparation made for 20 days of experiment in the blood contained more estradiol-17β (81.3 ± 4.0 pmol / l) and progesterone (37.7 ± 2.5 nmol / l) than Sidor stimulated pigs (75.7 ± 3.5 pmol / l; 31.1 ± 2.0 nmol / l) and in control animals (64.4 ±, 1 pmol / l; 28.1 ± 2.0 mol / l). The drug has a positive impact on the development of ovaries. In the pigs after stimulation in the 8-month-old age, the mass indicators, volume, linear parameters of the ovaries, as well as the number of follicles and the yellow bodies of the past sex cycle exceeded those in the control animals and pigs undergoing stimulation by Sidor.
Conclusion. Research suggests that the method developed by us allows us to obtain a natural genital cartridge pheromone preparation with high biological activity. As a natural stimulator, sex pheromones through olfactory analyzers have a stimulating effect on the relevant cerebral centers and through them to the hypothalamic-pituitary complex, which activates the growth and hormonal activity of ovaries. 

Purpose: to establish the effect of water-soluble liquid feed additives on the quality of the semen of roosters of the parent flock ROSS-308.
Materials and methods. The experiments were carried out in the period of 2020–2022 in the hospital of the veterinary clinic of the Faculty of Veterinary Medicine, Food and Biotechnology of the Saratov State Agrarian University. In the experiment, roosters of the parent flock ROSS 308 were used. To assess the quality indicators of the spermogram of the obtained ejaculates and determine the indicator of sperm activity, the selected roosters were divided into three groups: group 1 (n=5) - control; The 2nd group (n=5) of the experimental group received the Reasil Humic Vet feed additive with water, the 3rd group (n=5) of the experimental group received a product containing colloidal selenium, silymarin and a stabilizer (NKS) as nanoparticles.
Results. A fairly good volume of ejaculate was obtained from the experimental males, which ranged from 0.5 ml to 1.1 ml. The growth of sperm activity in the 2nd group and in the 3rd experimental group occurred on the 20th day and the next day of the experiment and showed a stable result from 8,5 to 9,5 points. As a result of the experience of studying the quality indicators of sperm in the 2nd and 3rd experimental groups of roosters, high Cv variability values from 32,0% to 54,0% were obtained. Established for the indicator of the concentration of active sperm in the ejaculate: in relation to the fertilization of eggs r = 0,67 ... 0,86, hatchability of eggs - r = 0,52 ... 0,70, hatching of chickens - r = 0,36 ... 0,51.
Conclusion. Given the high positive relationship between the concentration of active sperm in the ejaculate of roosters and the incubation qualities of eggs, it is advisable to use this indicator in breeding programs.

Purpose: analysis of changes in the structure of fur farming industries by the number of fur farms with different numbers of livestock for the period from 2011 to 2020.
Depending on the size of the livestock, farms are grouped into several groups: small, medium, large, large and very large. Given the prevalence of certain types of fur-bearing animals on farms, 5 groups were identified for mink, 4 for foxes, and 3 groups for arctic fox and sable.
For the period from 2011 to 2019 in the fur farms of the Russian Federation, there is a constant decrease in the number of minks (by 7.1%), arctic foxes (by 38.1%) and foxes (by 40.6%). During these years, the number of sables increased by 91.0%. Over a 9-year period, 12 mink farms, 5 fox and 6 arctic fox farms were liquidated. 6 new mink farms were formed, 2 fox, 4 fox and 4 sable. Despite the unfavorable state in fur farming, by 2019, in eight mink breeding farms, the breeding stock increased from 990 (Vyatka) to 27,501 (Furs) females of the main herd. A trend of enlargement of mink farms was noted. There is a decrease in the number of breeding stock on fox and arctic fox farms. In fox farming, after 9 years, 5 farms remained in the “large” and “large” groups (in 2011 there were 9), in fox farming, 3 farms remained in the “medium” and “large” groups (in 2011 there were 8). In sable breeding, an increase in livestock on 9 farms was recorded from 490 (“Russian sable”) to 5435 (“Magistralny”) females. In 2019, of all fur farms, only one belongs to the “small” group. For 9 years, the breed composition of certain types of fur-bearing animals has changed. The mink gene pool has decreased by three colors, the share of the brown group is decreasing, the share of color groups is increasing. In foxes, the share of the silver-black breed increased by 3.6%. In sable breeding, the share of the black sable breed increased by 1.8%.

Purpose: study of the effect of mineral nutrition on digestibility and the use of nutrients of rations. 
Materials and methods. Repair heifers served for research from 6- to 18-months of age. According to the methods of groups of analogues, two groups of heifers, black and motley breed were formed. The control group received a feeding diet adopted in the economy. Animals of the experimental group were fed by the ration with the optimal level of mineral substances. Contents binding. Feeding, watering is individual. The determination of nutrients of the rations was carried out according to the techniques adopted. 
Results. It has been established that the age of animals, as well as the balance of rations on the complex of the missing mineral elements, has a noticeable effect on the digestibility of nutrients. In repairing heifers with an optimal mineral feeding level, an increase in dry and organic matter, raw protein, raw fat, raw fiber, without nitrous extractive substances is marked. Increased digestibility coefficient of nutrients of the diet, namely dry and organic matter by 1,38% and 1,78%, crude protein 2,82% and 3,40%, raw fat, 3,21% and 2,65%, raw fiber 3,55% and 2,56%, without nitrous extractive substances – 0,7% and 1,33%. These physiological studies show that with age in animals, the use of nitrogen changes. So in 6-month-old heifers of the experimental group, the degree of nitrogen's absorption from the adopted with feed is 30,01%, from the digestible 44,9%. 18-month-old - respectively, from the age taken with the feed – 18,96%, from the digestive – 30,05%. This is due to the relative increase in the fiber diet and slowing the growth intensity of muscle tissue. The use of nitrogen varies also under the influence of the level of mineral substances in rations. Studies have shown that the replenishment of their deficiency in the rations of animals of the experimental group ensures an increase in nitrogen deposits in a body by 10,9-11,6%. The degree of its use (both from the feed and digested) was higher.