The use of “protected” fats in feeding cows provides the animals with the necessary amount of energy. One of the most guaranteed sources of energy in diets and feed mixtures of cows are rapeseed products. The article presents research materials, the purpose of which was to establish the effect of a complex energy feed based on dryprotected fat as part of rations for dairy cows during the period of increasing the milk yield on milk productivity and hematological parameters. Studies showed that the inclusion of energy feed based on dry protected fat in the diet of experimental animals in the amount of 3% by weight of the compound feed contributed to an increase in milk productivity by 8.1% and had a positive effect on hematological parameters.

The system of feeding young animals, especially in the first 30 days, should be aimed at preserving and strengthening the protective properties of the body, that is why the compound feed must contain a substantial proportion of vitamins, microelements and other biologically active substances. One of the available sources of these elements is frozen and native goat milk containing recombinant lactoferrin. However, such milk is produced in limited quantities, so it must be used rationally. This article presents the materials of scientific work, the purpose of which was to study the effect of the duration of feeding the goat milk containing recombinant lactoferrin on hematological parameters and productivity of pre-weaned calves. The best effect was obtained when feeding thawed milk of producing goats for at least 20 days: animal growth capacity and feed consumption efficiency increased by 3.3-8.3 and 2.3-4.9 %, respectively.

Complete feeding makes it possible to fully use the genetic potential of animals, increase productivity and reduce feed consumption. In order to balance diets in terms of protein, it is advisable to use synthetic nitrogenous substances in feeding ruminants, since this allows releasing a significant amount of high-protein plant feeds (oilcake, meal) in diets. The article contains the results of studying the effect of feeding nitrogenous substances of non-protein nature on the productivity of young cattle. It was found that the use of 10-, 20- and 25% carbamide concentrate in animal diets increased the degradability of protein in compound feed, blood erythrocyte level by 6.18-7.77%, hemoglobin concentration by 4.8-6.2%, leukocyte content by 10.3-13.3%, platelets by 4.1-21.5%, which contributed to an increase in the average daily gain by 6.8-11.9%.

When raising young cattle, the aim is to minimize the consumption of whole milk, using a variety of milk substitutes to ensure normal growth and development of calves. The purpose of the research, to which the article is devoted, was to develop the technology of feeding breeding heifers in the preweaning period, providing the normalization of metabolic processes in the body, as well as the improvement of feed use efficiency. It has been established that feeding calves aged 10-65 days with the whole milk replacer according to the developed scheme has a positive effect on feed intake and enhances redox processes. It was also found that the average daily gain in live weight of calves fed with whole milk was higher than that of counterparts consuming WMR by 3.7 % for the experiment. The cost of gain was almost the same.

Early inclusion of grain concentrates in the calves’ diet has a positive effect on accelerating rumen development, which leads to greater consumption and better digestibility of the grain starter mash, resulting in more intensive growth of the calf. The article presents research materials, the purpose of which was to study the effectiveness of the use of whole grain corn in feeding calves and determine the optimal rates of its inclusion in the diet. It was found that the inclusion of whole grain corn in the amount of 30 and 40% by weight of compound feed in the diet of calves aged 10-65 days had a positive effect on feed intake, contributed to an increase in average daily live weight gain of young animals during the period of experiment by 4.6 and 7.6% , while reducing the cost of feed by 2.4 and 4.1%, the cost of gain - by 5.4 and 8.3%.

Until recently, farms traditionally fed calves with dairy feed for 4 months, but the preweaning period can be reduced to 2-3 months. The main criterion for this is physiological development of calves and their ability to consume vegetable feed in the required quantities. The aim of the research was to develop the calf rearing system with the most effective duration of the preweaning period, ensuring the normal course of digestion processes and animal productivity. For this purpose, whole milk and dried skim milk replacers were developed. It was found that their inclusion in the diet instead of whole milk contributed to the strengthening of metabolic processes in the animals of experimental groups compared with the control counterparts. The use of dried skim milk and whole milk replacers when raising young animals during the preweaning period of 115 days reduced the cost of the diet by 10.3% and 5.8% and the cost of gain by 8.5% and 4.8%.

In the process of scientific work, the effect of extruded mixture of concentrates with a high content of degradable protein and non-structural carbohydrates on indicators of rumen digestion, productivity and efficiency of the dietary feed was studied. The objects of the study were black-and-white bulls at the age of 3-6 months. It was found that feeding them with grain mixture subjected to barothermic treatment contributed to a better growing capacity and efficiency of using nutrients in the diet. As a result, live weight gain in animals of the experimental group was 5.8 % higher than in the control group, and feed costs were 3.2 % lower.

Cows of Holstein breed, actively used in dairy cattle breeding of the Republic of Belarus, have high milk yields and, therefore, a higher requirement for nutritional components compared to bred animals of the Belarusian Black-and-White breed. The article contains the results of studying zootechnical and economic efficiency of the increased rates of phosphorus, magnesium, sulfur and vitamin D (up to 10 and 15 %respectively) in the diets of highly productive cows of the Holstein dairy cattle breed of domestic selection for the Belarusian Black-and-White breed in the 1st and 2nd phases of the dry period and in the 1st third of lactation. It was found that the developed standard requirements for the above nutritional components had a positive effect on productivity and milk quality, as well as homeostasis, digestibility of organic matter and the use of nitrogen in the animal body.

Fiber is necessary for ruminants to stimulate the activity of the rumen, keep healthy and maintain a certain level of milk fat content. Its deficiency or, on the contrary, its excess content has a negative effect on ruminants, therefore, when organizing feeding it is necessary to consider not only the level of nutrition of the animal itself, but also the microflora of its proventriculi. The article presents the results of studies on the qualitative and quantitative composition of the ruminal microbiota when using high-fiber diets in the winter. It was found that the average daily milk yield was lower when high-fiber diets (23.0-26.11%) were used compared to that of the preliminary period. There is also some quantitative increase in bacteria of such genera as Bacteroides , Bifidobacterium , Escherichia and a decrease in the number of bacteria of the genera Lactobacillus , Lactococcus , Streptococcus , which are important enough to maintain an optimal level of feeding.

Complete feeding of young replacement and adult breeding animals makes it possible to provide the diets of animals with the necessary nutrients, which have a positive effect on the semen quality and, consequently, increase the period of economic use. Therefore, the purpose of the study was to optimize the structure of diets for servicing bulls. It was found that feeding the experimental diets of winter and summer periods with the same type of feeding increased the ejaculate volume by 4.0-4.2%, sperm activity - by 3.1-6.4%, sperm concentration in ejaculate - by 13.8-15.3%.

The use of oil flax makes it possible to reduce the deficiency of fodder protein in the diet and balance the protein nutrition of animals. The article contains the resultsof scientific work, the purpose of which was to determine the effect of feeding oil flax cake on the efficiency of young cattle fattening. Studies showed that the use of different levels of oil flax cake in the compound feed had a positive effect on the productivity of fattened animals. Higher live weight gain and relatively low feed costs contributed to a decrease in price cost of rearing products by 8.7-10.8% during the period of the beginning of young cattle fattening.

In conditions of industrial livestock farming, the adaptive stress on the animal body increases, which causes metabolic disorders, weakening of immune system and, eventually, a decrease in animal productivity. Balanced feeding of animals allows to regulate lipid metabolism, in particular, through the use of phospholipids in diets. The article contains the results of the study of the effect of the feed additive “Lecithin C” on the hematological parameters of young cattle. Studies have shown that the use of the additive under discussion in different concentrations has a positive effect on the morpho-biochemical composition of the blood and normalizes metabolic parameters.

The negative impact of a complex of technological stress factors on the body of young animals determines the use of new biologically active substances in diets that can prevent their adverse effects. Lipids, which are the most concentrated source of energy, can become an alternative to feed antibiotics as growth promoters. The article contains materials of the study of the effectiveness of using different dosages of the new feed additive “Lecithin C” in diets of young cattle. Studies have shown that the use of the feed additive in the compound feed concentrate KR-3 in amounts of 6.5 g,and 19.5 g per head per day contributes to an increase in dry matter intake by 1.9-7.5% and metabolizable energy by 2.2-6.5%, increases average daily productivity, provides a reduction in the cost of feed consumed per 1 kg of gain, and the cost of gain by by 3.9-7.1%.

The article presents the results of research aimed at studying the effect of technological equipment for the production and primary processing of milk on its physical and chemical parameters. In terms of bacterial contamination, better milk was obtained from a group of cows at Сommercial dairy farm (CDF) No. 7, where fine filter was used. The milk corresponded to the “Extra” grade. When cows were milked in the milking parlor at CDF No. 7, this indicator was 11.0 thousand CFU/cm3 lower (at P<0.05) compared to CDF No. 5. As a result, 74.5% of milk produced at CDF No. 5 and 84.1% of milk produced at CDF No. 7 was sold as the “Extra” grade.

The aim of the research was to establish an effective option for raising and fattening cattle for meat in Belarus. The article analyzes options for organizing the work of complexes for raising and fattening cattle of different capacities on the basis of empirical, industrial and statistical materials. It has been established that with a change in the number of animals, the following pattern is observed in terms of production period, production rhythm, the number of stockings per year and the size of the production group: with an increase (decrease) in the average daily gain by 100 g, the production rhythm decreases (increases) by 1 day. With an increase in the turnover of cattle places during the year and a reduction in rhythm, beef production will increase by 8.7-74.3 tons (with average daily gains of 1000 g).

The article presents the results of research aimed at studying the effect of different lengths of milk hoses for pumping milk from the milking parlor to the cooling tank on the sanitary and hygienic indicators of milk. In the course of the work, the influence of different lengths (internal surface area) of milk transfer hoses on the total bacterial contamination of milk samples from a single milk yield was determined. In terms of titratable acidity, mechanical contamination and somatic cell content, milk corresponded to “Extra” grade.

Machine milking technology requires a strict selection of cows, because different factors influence its efficiency: physiological characteristics of animals, technical characteristics of milking plants, etc. In this connection, the purpose of our research was to study udder quality and to establish the influence of teat morphological features on the process of machine milking. It was found that 75% of the herd had cylindrical teat shape, which contributed to complete udder emptying, there was no teat canal overcompression in the upper part, the cows did not show anxiety. At the same time, animals with funnel-shaped and conical udders were identified (15.9 and 9.1%, respectively). When milking these cows, the teat canal in the upper part was clamped by the rigid edges of the teat rubber, which slowed down the process of milking. When milking these animals, it is recommended to use teat rubbers with soft edges of the head, which can increase the average and maximum milk flow rates of cows by 12.5 and 7.5% respectively and relative milk yield by 3.3 percentage points.

The main task of the Belarusian cattle breeding is to increase the production of milk and beef, as well as to improve the economic efficiency of the industry. Our research in the form of industrial experience of comparing technological schemes for obtaining commercial dairy products, carried out in the operational environment of Miropolye (OJSC), showed that in order to improve the efficiency of the industry, it is necessary to reconstruct old livestock buildings, which will make it possible to enhance quantitative and qualitative characteristics of manufactured products, optimize the milk production resourcing and return on investment. This allows for improving the milk production process and increasing the volume of output by 17.7%, thereby creating preconditions for enhancing the efficiency of using the resource potential of the enterprise and biological characteristics of animals, reaching the milk production profitability level of 31.3%.

Directional rearing of replacement young animals in compliance with all technological parameters is the most important part of the technological process forproduction of hatching eggs. The success of any specialized poultry farm largely depends on the correct organization of this process. The article describes the technology of rearing replacement young birds and parental forms of broilers in the production conditions of Agrokombinat Dzerzhinskiy OJSC. The use of all rearing methods and parameters within this technology will allow achieving high production and economic indicators in any specialized poultry farm of the republic.

The preservation of young animals and their resistance enhancement in the early postnatal period is a significant reserve for increasing the production of livestock products. The article presents the results of studies of the influence of the duration of keeping calves in individual houses on their natural resistance and state of health. It has been established that during the initial postnatal period, newborn calves retain the state of hyporesponsiveness, which gradually forms with age. Therefore, it is most appropriate to transfer calves from individual houses to group sections after stabilization of the formation of the body’s natural defenses, that is, not earlier than 30 days of age. With the duration of keeping young animals in individual houses for more than 30 days, there were fewer sick calves by 20-40% compared with counterparts who were transferred to group housing at the age of 20 days.

Prophylactorium calf housing stage plays an important role in the formation of the body’s defenses. The article presents the results of research aimed at studying the influence of the duration of keeping calves in individual houses on their performance and comfort. It was found that with an increase in the duration of keeping calves in individual houses up to 30 days, the average daily gain in live weight increased by 3.8% in the first three months of life, with an increase in the duration of keeping calves in individual houses up to 45-90 days - by 5.1-6.7% compared to calves kept in individual houses for 20 days. When transferring calves to group sections at the age of 20-45 days, they relatively quickly adapted to external conditions, actively moved. Thus, the transfer of calves to group housing at the age of 30-45 days makes it possible to create more comfortable conditions that meet their biological needs.

The article presents the results of bioenergetic analysis of milk production at commercial dairy farms and complexes of different capacities. The objects of the study were commercial dairy farms and complexes of State Enterprise “ZhodinoAgroPlemElita” of Smolevichi district, which have a complete cycle of milk production. Studies have shown that the implementation of milk production technology at the CDC “Berezovitsa” with a capacity of 850 heads requires less energy than at the CDF “Zhazhelka” with a capacity of 750 heads and the CDC “Rassoshnoye” with a capacity of 1000 heads.

The aim of the work was to determine the prospects for increasing the economic efficiency of milk production with different duration of the service period. Based on research carried out in the conditions of 4 agricultural organizations in the Vitebsk and Mogilev regions, it has been found that cows with a service period of 61 to 90 days are characterized by higher milk productivity. Economic efficiency of milk production from cows with different duration of service period shows that with the duration of service period not less than 61-90 days the level of profitability of milk production increases by 7.3-9.4 percentage points.

An increase in milk productivity of cows depends not only on the genetic potential of animals and feeding, but also on the milk production equipment used. Milk production on any livestock farm depends on the efficiency of the technological system of machine milking in the chain “animals - milking machine - service personnel”, i.e. milking equipment must maximally correspond to physiological and morphological properties of cows’ udders, and the operation procedures must be followed. The paper presents the results of research on the effectiveness of using the UID 07.000 and Stimopuls MA milking machines in the technology of machine milking of Black-and- White cows kept in tie-stalls. Their influence on physiological properties of cows’ udders was determined. It has been established that the use of Stimopuls MA milking machines makes it possible to more fully unlock the potential of animals, increase productivity of dairy herd by more than 5% and thereby reduce the cost of production.

The production of meat products requires significant direct and indirect water expenditures. Our research was aimed at improving technological methods to reduce the consumption of process water during the growing-finishing phase in young pigs. It was found that the use of technological method to reduce the consumption of process water for manure removal, which consists in reducing the level of filling baths with water in the first growing-finishing phase to 0.05 m, in the second phase - to 0.07 m, allowed to reduce the average daily water consumption by 36.8% compared to the normal operation of a self-alloying intermittent manure removal system. At the same time, the temperature-humidity conditions and gas composition of indoor air corre- sponded to the normative requirements.

It has been established that digital twins are based on identified dependencies and mathematically formalized regularities, and use boundary conditions, curvilinear and nonlinear functions of parameter relationships in the calculation algorithm design. The main goal of developing digital twins is to fully reproduce a particular process through numerical values that can be easily verified (confirmed or disproved) by independent researchers based on their professional knowledge. In this case, researchers act as software testers in the IT field, that is, professionals involved in testing a component or system.

According to the materials of the article, the digital twin of objective control of the agricultural enterprise should be based on monitoring the enterprise’s current account, on accounting entries, on the analysis of waybills, etc. Moreover, objective control should be carried out in real time by persons concerned with the obligatory informing of all employees of the enterprise. The temporal equality of two technological periods is justified: suckling, completion of growing, fattening of young pigs and rearing of replacement gilts, their insemination and pregnancy. The regularity in the equality of the two technological periods is the basis for the implementation of self-developing type-related technology (ST-technology), one of the elements of which is the exclusion of the group of main sows from the production cycle and the transfer for slaughter of the first-litter sows, from which suckling piglets are weaned.

The importance of microelements and vitamins in animal nutrition is extremely high, only with their sufficient amount the animal body is able to fully use the nutrientsin the feed, maintain health and give the maximum productivity. We have established the positive effect of the complex iodine-selenium-containing prophylactic preparation “Iodis-vet” on the immunological properties of colostrum and milk productivity of cows in the interlactation period. The studied preparation also contributes to the increase of average daily milk yield. The best results were obtained when using it at a dose of 125 ml per head per day. The mass fraction of protein increased by 3.4%, the amount of immunoglobulins - by 8.04%, the milk yield for the entire period of lactation - by 7.09%.

Various factors influence the milk productivity of cows. The article presents the results of studies conducted in the APB “Zaozerie” of JSC “Vitebsk Meat Processing Plant” on 326 cows with completed lactation. In the course of scientific and economic experiment, it was found that the highest milk yield of 8417 kg was obtained from the cows of the 3rd lactation, with a significant increase in milk fat to the level of 316.4 kg. Gain in the live weight of cows in the herd to 651-700 kg contributes to a significant increase in their milk productivity to the level of 8430 kg of milk with a milk fat yield of 312.1 kg. The highest milk yield was obtained from cows with a dry period of 51-70 days - 9415 kg of milk (p≤0.001) with a milk fat yield of 358.7 kg and with a service period of 61-90 days - 7675 kg of milk with a milk fat yield of 285.5 kg (p≤0.001).

The article presents the results of studying the physicochemical and technological parameters of meat obtained from the carcasses of fattening young pigs of different delivery weights. The subjects of the study were the results of slaughter of two-breed crosses of young Yorkshire × Landrace (Y × L) fattening pigs with a delivery live weight of 80-100, 100-120 and 120-140 kg. It was found that per 100 kg of pre-slaughter weight, the cost of products obtained from individuals with a delivery weight of 100-120 and 120-140 kg was higher than that of animals with a weight of 80-100 kg by 3.1 and 8.6 %, respectively, due to a higher yield of high-priced products.

According to the results of three-year research in the center of genetics and selection of the Grodno regional breeding enterprise, the main reasons for culling of service boars (diseases of tendons, joints, digestive organs, cardiovascular system) and the influence of their breed affiliation on the age of removal from the herd due to diseases, reduced productivity were established. The average age of culled Yorkshire, Landrace and Duroc boars was: 33.3, 31.2 and 29.9 months due to tendon diseases, 35.8, 40.8and 30.2 months due to joint diseases, 37.5, 35.0 and 27.0 months due to cardiovascular diseases, respectively. The average age of boars culled in terms of sperm production quality was: Yorkshire - 25.9 months, Landrace - 38.8 months, Duroc - 29.7 months. The average age of pigs culled due to old age in the Yorkshire breed was 71.9 months, in the Landrace - 64.8 months.

The article presents the materials of studies, the purpose of which was to conduct a bioenergetic assessment of technological solutions and a set of process equipment used at seven operating farms and complexes for beef production of various capacities. It was found that the technologies used at the complexes in Agricultural Production Cooperative (APC) “Ostromechevo”, APC “Progress Vertilishki” and JSC “Vasilishki” were the most preferable for all indicators. The coefficient of bioenergy efficiency was 15.61%, 15.34 and 15.49%.