Relevance. For the reproduction of the breeding stock of cattle, the conditions of detention should maximally meet the optimal conditions for the life of animals. In this regard, the study of the characteristics of physiological changes after injections of bioregulators to induce estrus in cows under various systems and methods of keeping is of great importance and is an important area of research. The purpose of the work is to study the reproductive function of cows depending on age and various conditions of keeping.

Methods. The results of the work are based on analytical, biometric, statistical methods and the authors’ own research.

Results. In studies was found that a general decrease in the effectiveness of the use of GnRH analogs and hCG to increase fertility can occur due to treatments carried out in the summer months. The greatest effect of the use of GnRH and hCG preparations should be expected when they are introduced in parallel with insemination in induced estrus in the winter-spring and autumn-winter months. At the same time, the fertility rates in cows tethered were slightly higher in the stall-pasture system of keeping, and slightly lower in the camp-pasture system than in loose ones. When studying the reproductive function, depending on the number of lactations, as a result of the use of a complex of bioregulators, high indicators of cows that came into the hunt were obtained, from 74 to 91% of the total number of animals showed signs of estrus according to the different number of lactations. Cows with 1st and 2nd lactation have the highest rate for those who came into heat (91% and 87%) with the lowest insemination efficiency (47% and 49%, respectively). In cows of the 3rd and 4th lactations, the highest adjustment to the restoration of the ovarian cycle is observed, with the average indicators of those who came to the hunt, the highest insemination efficiency was subsequently obtained (70 and 75%, respectively). For three or more months after calving, more than half of the herd of calving cows (71.6%) were fruitfully inseminated.

Relevance. Chemoprophylaxis of piroplasmidosis of cattle in disadvantaged farms due to the lack of vaccination is carried out mainly with the use of DAC, Neosidin. It was found that polyethylene glycol prolongs the preventive effect of these drugs for 20–21 days, naganin with polyvinylpyralidone — for 25 days. Carrying out of treatments with such intervals during the disease season is unacceptable, since it adversely affects the state of the animal organism, contributes to the emergence of resistant types of pathogens and leads to unjustified consumption of drugs. In this regard, finding the treatment and prevention of piroplasmosis of cattle is an urgent task.

Materials and мethods. The comparative prophylactic effect of chemotherapy drugs in piroplasmidoses was studied on 45 animals, which were divided into 3 groups (15 heads). The first group (n = 15) served as control; Neosidin 7% was used at a dose of 3.5 mg/kg. In the second group (n = 15) animals were injected with Neosidin 7% in dose 3.5 ml/kg, with polyethylene glycol (PEG) 20 g per 100 ml of water. The third group (n = 15) was injected with Forticarb at a dose of 2.5 mg/kg at the rate of 2.5 ml/100 kg of live weight, once, intramuscularly. Animals were observed during 40 days. Sick were treated with Forticarb, in dose 4 ml/100 kg.

Results. For the first time under production conditions, the preventive efficacy of Forticarb in piroplasmidoses of cattle was studied, which is manifested by increased safety and obtaining of additional products during the season of diseases. The results showed that the drug Forticarb protects animals during 30 days from diseases.

Relevance. In the available literature, there are enough works devoted to the study of pathomorphological changes in low pathogenic influenza. The described changes are not sufficiently systematized, including in laying hens.

Methods. The material for the research was the corpses of 60 laying hens, 235–428 days old, egg crosses “Tetra”, “Hisex Brown”, “Dekalb White”, killed for diagnostic purposes. Research methods: autopsy, histological examination.

Results. Leading macroscopic changes: cyanosis of the comb and earrings; acute serous-catarrhal rhinitis, laryngotracheitis; acute fibrinous-purulent sinusitis; acute catarrhal or fibrinous-hemorrhagic pneumonia, pulmonary edema; yolk peritonitis; granular and fatty degeneration, acute venous hyperemia of the liver, kidneys and myocardium; hemorrhages in the epicardium. The most characteristic histological changes: necrosis and desquamation of the integumentary epithelium of the larynx and trachea, inflammatory hyperemia, fibrinoid swelling of the walls of the vessels of microvasculature, hemorrhages, serous edema, pronounced lymphoid-macrophage and plasma cell infiltration of the mucous membrane; croupous pneumonia with a pronounced hemorrhagic accent, lymphoid-macrophage infiltration of the mucous membrane of the bronchi and parabronchi of the lungs, fibrinoid swelling of the walls of the vessels of microvasculature, hemorrhages, emphysema; hemorrhages in the serous membrane of the esophagus, in the mucous membrane of the duodenum, jejunum, ileum and caecum; acute venous hyperemia, serous edema, granular, smalland large-drop fatty degeneration of hepatocytes of the liver, fibrinoid swelling of the walls of the vessels of microvasculature, hemorrhages; acute venous hyperemia of the kidneys, serous edema, large-drop fatty and vacuolar degeneration of the epithelium of the urinary tubules, fibrinoid swelling of the walls of the vessels of microvasculature, hemorrhages; acute alterative myocarditis; fibrinoid swelling of the walls of the vessels of microvasculature of the spleen, hemorrhages; acute venous hyperemia of cerebral vessels, pronounced perivascular and pericellular edema.

The publication outlines the results of antigenic activity trials for experimental samples of a marker vaccine against classical swine fever (CSF) prepared using different types of adjuvants, as well as data on the duration of immunity upon administration of this vaccine to laboratory and naturally susceptible animals. Live vaccine “KS”, widely used for the specific prophylaxis of CSF in Russia, was used as positive control. The data obtained indicate that all experimental samples of the vaccines stimulated a pronounced immune response to CSF viral glycoprotein E2, triggering off production of virus-neutralising antibodies in immunised piglets. Antibodies possessing such specificity were detected in piglets in high concentrations over a period of 96 days after double vaccination up to the final day of the experiment. Experimental samples of the vaccine did not induce synthesis of antibodies to CSF viral glycoprotein ЕRNS, which would allow one to use the vaccine and be able to distinguish vaccinated animals from those naturally infected with field strains. This strategy, by consequence, will be valuable in the implementation of CSF eradication programs.

The purpose of the study is to study the features of treatment and rehabilitation of horses with tendovaginitis in the conditions of an equestrian complex. The experiments involved 2 groups of horses that received tendon ruptures of different etiologies. The diagnosis of limb injuries was carried out based on anamnesis, clinical signs, ultrasound and X-ray studies. Treatment of all horses was carried out according to the scheme adopted at the MCSC “Kazan”. During complex therapy, the course of the process was monitored and the formation of an “arc” on the limb, thickening and consistency, soreness, the presence of edema, and an increase in local temperature were taken into account. As rehabilitation measures, free walking, walking, handwork, massage were prescribed. Additionally, hydromassage was used (water temperature 30–37 °С) above and below the injury site. All the horses were kept in the same conditions of the racetrack. The results obtained show that in addition to treatment for tendovaginitis, physical rehabilitation has become necessary to restore the normal volume of movements, ensure mobility, and dynamic stability of the limbs. The main principles of rehabilitation are: early initiation of rehabilitation measures, comprehensive use of all available and necessary means, individualization of the program, compliance with stages, continuity and succession throughout all stages of rehabilitation. The rehabilitation plan should be based on the assessment of functional disorders and the stages of the regeneration process. The rehabilitation program developed by us included kinesiotherapy, manual massage and hydromassage (water temperature 30–37 °С). The horses, who underwent daily rehabilitation measures, completely restored their damaged limbs and returned to a sports career.

The effect of two forms of selenium, inorganic and organic, was evaluated in the study. Lactating cows of the 1st control group were fed 4.9 mg/head/day of inorganic form of selenium, cows of the 2nd, 3rd and 4th experimental groups received organic form of selenium in the amounts of 2.5, 3.7 and 4.9 mg/head/day. Researches show that application of organic form of selenium permits to increase average daily milk yield by 3.3, 12.9 and 10.8% (р < 0.05), while increasing of dry matter concentration in milk by 0.57% (р < 0.05) in comparison with the 1st control group. When administering selenium in organic form 3.7 mg/head/day, there was a tendency to increase in amount of casein and decrease in amount of somatic cells in milk by 0.13% and 33.7 thousand/ cm3 respectively (р < 0.1). A dose of 4.9 mg/head/day of organic selenium contributed to a decrease in amount of somatic cells by 29.3 thousand/cm3 (р < 0.05). Feeding experimental groups with organic form of selenium in different doses had a positive effect on the immune status and antioxidant activity of blood serum. The content of free water-soluble antioxidants (TAWSA) in blood serum was higher by 39.3 and 53.5% (р < 0.001) in cows of the 3rd and 4th experimental groups fed 3.7 and 4.9 mg/head/day of organic selenium. Thus, the use of selenium in organic form is the most effective and allows to reduce the amount of used micronutrient for replenishment of animal needs.

The North-West region of the Russian Federation is characterized by high weed infestation and large yield losses of spring barley. At the same time, the use of herbicides in agrocenoses of spring barley with perennial grasses oversowing has its own characteristics. The aim of the study was to determine the effectiveness of herbicides Agritox, VK and Bazagran, VR against weeds in the agrocenosis of spring barley and their effect on the growth of perennial grasses during current and next years. The studies were carried out at the agroecological station of the Menkovsky branch of the Agrophysical Research Institute, located in the Leningrad region, during 2012–2019. The studies have shown significant differences in the effectiveness of herbicides Agritox, VK and Bazagran, VR in relation to weed species common in agrocenoses of spring barley with oversowing of perennial grasses in the North-West of Russia. The herbicide Agritoks, VK turned out to be less effective against stickwort and common nipplewort, and Bazagran, VR — against white goosefoot, field pansy, common fumitory and hemp-nettle. Under conditions of moisture deficit and high average daily temperatures, the herbicide Agritox, VC induced a phytotoxic effect on red clover plants, which was reflected in the accumulation of the vegetative mass of perennial grasses both in the year of growth under the cover of barley and in next years as a targeted use during hay production.

The main agrotechnical significance of crop rotation is that each crop is placed in the best conditions for its growth and development and at the same time prepares good conditions for the next crop in the crop rotation. Under optimal cultivation conditions and a high level of mineral nutrition, the grain yield of modern wheat varieties reaches 18.4 c/ha. In real economic conditions, when high prices for mineral fertilizers limit their use, the yield of spring wheat grain in the Kostanay region is 11.2 c/ha. In the experiment, 2 types of crop rotations were studied — 4-course grain-fallow (fallow— wheat — wheat — wheat) and 4-course fruit-shifting (peas — wheat — oilseed flax — wheat). On each crop rotation variants with different levels of mineral nutrition were laid — without fertilizers (control) and P15. Seeding rate of agricultural crops (million/ha of germinating seeds): spring wheat — 3.0; peas — 1.0; oilseed flax — 6.0. The experiment adopted the technology of tillage — No-till with elements of precision farming. All records and observations were carried out according to standard methods. The analysis of the dynamics of the food regime of the soil indicates that the best conditions for mineral nutrition of plants are created when placing crops in a grain-fallow crop rotation, which includes herbicidal steam with long-term annual application of mineral fertilizers. Thus, in the soil layer of 0–40 cm on the first wheat after fallow, the content of nitrate nitrogen was characterized as average and amounted to 11.9–12.8 mg/kg, the content of mobile phosphorus had increased and amounted to 121 mg/kg of soil. In terms of the effectiveness of the use of options for the purpose of regulating the food regime, it is necessary to distinguish all three wheat fields in the grain-fallow crop rotation. Here, the highest indicator in the earing phase — above the control by 6.1–14.7% — was in variants with the use of fertilizer in rows.

Recently the orientation on fertilizers of agrogenous origin (leies, straw, crop residue) is significantly expanding. As the main agricultural instrument, ensuring the achievement of these goals, scientifically based crop rotation is adopted as a method for regulating the receipt and quality of organic matter into the soil and the speed of its transformation. In this regard, our research is aimed at developing the optimal structure of field and crop rotations for a developing situation. The cultivation technology of crops was generally accepted for the research area. Placing options were: (A) sequential and (B) blocks in three tiers. The main soil cultivation in the experiment was beardless plowing by stilt SibPME to a depth of 25–27 cm. Regionalized varieties of agricultural crops were cultivated. The counts and observations were carried out according to the recommendations. For the period July — August, the largest amount of precipitation fell in 2016 — 119.0 mm; the smallest in 2017 — 6.0 mm, in other years this indicator was in the range of 32.8–86.0 mm. On average, over the years of research, the greatest accumulation of crop residues, straw and roots was in a 4-field crop rotation with black fallow — 3.4 t/ha. The highest amount of nitrogen entering the soil with straw, crop residues was noted in an 8-field crop rotation — 49.8 kg/ha. The largest amount of biological nitrogen (according to Trepachev’s method) was accumulated under alfalfa crops — 34.4 kg/ha. Analysis of soil samples for the content of humus over the years of research did not reveal significant changes. The best predecessor for winter wheat is black fallow. After perennial grasses, peas, the grain yield of winter wheat in some years decreases by 4–12 c/ha. Analysis of the correlation dependence of the productivity of crop rotations has shown that the highest dependence with atmospheric precipitation for May — June is t = +0.50 for grain and fodder units and slightly less — for protein (t = + 0.26–0.50).

Biologization of crop production, aimed at the predominant use of biological factors to increase the economic efficiency of agricultural production, is becoming the main direction of increasing soil fertility and obtaining high guaranteed yields of agricultural crops. Currently, the actual trend in the development of organic farming is the support and restoration of soil fertility, primarily through the use of green fertilizers. One of the new types of field crops used as a phytomeliorant is safflower. According to the morphological characteristics of the genetic horizons of the profile and the agrochemical parameters of the arable layer of the soil of the experimental plots, they are characteristic for dry steppe zone of Western Kazakhstan. In the experiment, safflower crops (Carthamus tincforius) were studied as a phytomeloriant. The area of the plots is 50 m2, the replication is threefold, the location of the plots is systematic. The seeding rate of safflower seeds is recommended for the dry steppe zone of the West Kazakhstan region. The green mass of safflower as a green fertilizer was plowed into the soil during the periods of it's flowering with disc harrows. As a result of the study, an assessment was made of field crops of yellow mustard and safflower cultivated in the organic farming system for phytomeloration of dark chestnut soils. Studies have shown that in the 0–2 cm layer of dark chestnut soils under the influence of the phytomeliorative action of safflower, an increase in the content of nitrate nitrogen from 5.08 to 5.35 mg/100 g of soil, or by 5.31%, was noted by autumn. During the spring — autumn period, in the 0–20 cm layer of dark chestnut soils, the content of mobile phosphorus increased from 1.17 to 1.22 mg/100 g of soil, or by 4.27%. Sowings of safflower had a positive effect on the agrophysical indicators of dark chestnut soils. In studies, soil loosening by 0.020 g/cm3 and an increase in structure up to 64.47% were established.

Relevance. The level of technical equipment occupies a special place in the development of agricultural production. For the development and improvement of production operations in agriculture, developed countries are introducing various high-tech processes and equipment. As a result, agricultural work becomes more interesting, productive and efficient. Only due to the complete automation of technological operations and processes, it is possible to significantly facilitate hard physical labor. The volume of work is significantly increasing at the same costs with the use of innovative machinery and equipment in agricultural production. Consequently, this leads to an increase in the economic efficiency of production.

Materials and research methods. The materials of the study were data from periodicals on trends in the technical re-equipment of agriculture in Russia, materials of statistical reporting of the Russian Federation, its constituent entities and the Ministry of Agriculture of Russia over the past decades. In the course of the research, abstractlogical, monographic, computational-constructive, comparative analysis and statistical methods were used.

Results. According to the results of the studies, it was established that the provision of agricultural machinery and equipment to agricultural enterprises in Russia has been deteriorating from year to year since 1990, there is a high level of deterioration of technical equipment, a low level of its renewal, a large share of old structures in the structure of the technical fleet of agricultural enterprises. Due to the lack of agricultural machinery, Russia loses about 30% of its crop yield every year, significant losses of production occur from non-compliance with agrotechnical terms for spring sowing, sowing winter crops, harvesting, as well as violations of the technology of cultivation of crops. As the reasons for the lag in the technical equipment of agricultural enterprises in Russia, the authors highlight such factors as the low level of profitability of agricultural enterprises, the inaccessibility of credit funds and weak government support for the industry. It is proved that without positive changes in the trend of technical equipment of agricultural organizations it will be impossible to increase the efficiency of agricultural production.

The issues of competitiveness of agricultural organizations at the present stage are relevant, since the achievement of competitive advantages based on the optimization of processes in the field of finance, production, marketing, human resources management is one of the key elements of the entity’s activities. The competitiveness of agricultural organizations can be influenced by many factors, both macroeconomic and microeconomic. In this regard, it becomes necessary to determine the main factors of the competitiveness of organizations in the agricultural sector. The purpose of the study is to develop a multifactorial model of the competitiveness of agricultural organizations. The formation of the correlation-regression model of competitiveness was carried out on the example of agricultural organizations of the Ulyanovsk region.