Researches aimed at increasing the fertilizing ability of semen of producing animals were conducted on boars and sows of Yorkshire breed of 16-30 months of age managed at SC “Rassoshnoye” of SE “ZhodinoAgroPlemElita” in Minsk region. As a result, a method has been developed to intensify motility and strengthen the cytomorphological integrity of spermatozoa by means of a complex biophysical effect on the biomaterial of producing boars allowing to minimize the decrease of spermatozoa motility during storage, increase the integrity of spermatozoa membranes, which promotes improvement of fertility rate by 10-20% and multiple pregnancy rate by 10 %.

The paper presents data of study of effects of highly concentrated cryoprotector solutions on mammalian embryos obtained in vitro . The 30% solution of ethylene glycol was determined to have the greatest protective properties. When using this solution, the safety of embryos after thawing is at the highest level among all the cryoprotectors studied - 88.2%, which is 5.8, 17.6 and 8.2 percentage points over compared with 30% solution of glycerol, 20% solution of dimethylsulfoxide and 10% solution of 1,2-propanediol, respectively. When using the 30% solution of ethylene glycol, the maximum level of embryo material cleavage after thawing and cultivation in incubator is 80.0%, which is 1.4-5.0 pp higher among all the studied cryophilactics.

The paper presents the results of study of effects of various complexes of cryophylactics on safety and viability of mammalian embryos obtained in vitro during freezing and thawing. It was determined that mixture of 20% DMSO solution and 20% EG solution along with 0.7 M sucrose used as cryoprotector allows to ensure the maximum embryos safety and maximum level of cleavage after thawing - 88.2 and 80.0%, respectively. Complex of cryophylactics consisting of 20% solution of DMSO, 20% EG solution and 30% solution of sucrose shows the highest protective properties: using this complex allows for preservation of embryos after thawing at the maximum highest level among all the studied complexes cryophylactics (88.9%) with a high level of embryo material cleavage after depreservation (75.0%).

The paper summarizes work on genetic determination of mutant shapes of poultry comb, and, in comparative aspect, the pheno-pool of domestic and imported poultry breeds is provided according to this marker. pleiotropic effect of a series of R-r alleles on reproductive TRAITS of Poltava clay hens is described. Efficiency of using gender differences for comb size to determine the gender of young broilers and chickens of Borkovsky meat and egg population is shown. The average accuracy of sexing of 5-week-old young meat and meat-and-egg stock according to the comb phenotype made 100.0% at sorting speed of about 1000 animals/hour. Complex genotypes of various comb phenotypes and the general layout of hereditary control of variability of head skin appendages shapes in representatives of four species of Gallus species are presented.

Maternal breeds of pigs were evaluated according to marker genes of reproductive, fattening and meat performance. The research subject was populations of purebred animals of Belarusian large white, Belarusian black-and-white and Belarusian factory type Yorkshire breed of pigs which were managed at agricultural branch of SGC “Zadneprovsky” of OJSC “Orshansky bakery products factory”, OJSC “SGC Zarechye” and OJSC “SGC “Zapadniy”. Analysis of polymorphism of individual gene markers of performance traits showed that animals of maternal breeds had rather high content of the desired alleles in the genome that determine reproductive and meat traits with a relatively low level of fattening traits. Predisposition of Belarusian large white and Belarusian black-and-white breeds to colibacteriosis was determined as well.

The paper presents analysis of genetic testing results, determines the frequency of alleles and genotypes of marker genes for the performance traits of lines and related groups of boars of Belarusian large white breed at agricultural branch of SGC “Zadneprovsky” of OJSC “Orshanskiy KHP” according to the genes of: ryanodine receptor (RYR 1), estrogen receptor (ESR), ECR 18 and H-FABP receptors, as well as insulin-like growth factor 2 (IGF-2). In the tested animal lines and related groups according to the Ryr 1 gene, the frequency of occurrence of the desired N allele made 0.992; undesired n - 0.008. The frequency of the desired IGF-2 gene allele A in the pig genome is low and averages 0.29. The frequency of the desired B allele of the ESR gene in the pig genome of Belarusian large white breed makes 0.44%. Analysis of the results of genetic testing of sows of the breed showed that the frequency of ECR F18 gene genotypes was as follows: АА - 2.1 %, AG - 39.1%, GG - 58.8 %. The frequency of the desired allele A made 0.21^** and varied from 0.15 to 0.25 depending on the linear origin of animal. It was determined that the frequency genotypes of H-FABP gene in pigs of the breed made: DD - 10.6 %, Dd - 42.9 %, dd - 46.5 %, HH - 80.0 %, Hh - 12.5 %, hh - 7.5 %. The frequency of the desired alleles d and H is quite high - 0.63 and 0.86%, respectively. It was decided to differentiate the animals of the breed, taking into account the polymorphism of marker genes of performance traits and their productivity, into maternal and paternal lines with separate selection and different standards.

The bulls of different lines of Holstein breed of Black-and-White and Red-and-White color were evaluate according to the level of dairy performance of their daughters, cows of Ukrainian Black-and-White and Ukrainian Red-and-White dairy breeds. It has been determined that parental origin had a more significant effect on performance of daughters' cows compared with the line. The offspring of bulls of the same line within each breed was characterized by a significant differentiation of dairy performance, which could be consistent with both the breeding value of the bulls and environmental conditions. Bulls have been identified that provide progeny with a high level performance in each of the breeds studied.

The paper presents analysis of the results of spermatozoa capacitation according to morphological indicators, obtained in different seasons of the year. It was determined that in semen obtained in the autumn-winter period, before capacitation from Lexus, Balero, Morphine, this indicator was at a lower level compared to spring-summer period. The difference made 0.1. For Barry and Rank it was on the same level. After capacitation, the teratozoospermia index improved by 0.1 in Barry and Rank bulls’ spermatozoa obtained in the autumn-winter period, and in Balero and Morphia bulls - by 0.1 in spermatozoa obtained in the spring-summer period, the teratozoospermia index did not vary in the Lexus bull.

The paper presents the results of studies on the effect of folliculogenesis regulation on the efficiency of oocyte aspiration. The analysis of the obtained data shows that the removal of follicles with a diameter over 8 mm does not affect the efficiency of oocyte aspiration. Quantitative and qualitative indicators in the experimental group did not differ from the control one. Removal of the dominant follicle in 72 hours before aspiration, allowed to increase, calculated per one aspiration in comparison with the control, the number of aspirated follicles by 41%, yield of oocytes - by 22.9%, including oocytes suitable for cultivation - by 30.8%. Ovarian stimulation with “FSG Super” preparation increased the number of aspirated follicles by 19.2-39.8%, yield of oocytes - by 32.8-45.9%, including oocytes suitable for maturation - by 39.6-43.7%. “Pluset” preparation increased the number of aspirated follicles by 35.9%, yield of oocytes - by 35.3%, including those suitable for maturation - by 43.9%.

A variety of breeding composition and genealogical structure of breeding groups of horses in equestrian organizations of Belarus has been determined. Dependence of breeding value of offspring on the individual compatibility of parental pairs, correlation of young animals’ efficiency at factory trials with its subsequent achievements in equestrian sport are shown. The number of winners in equestrian sports made 61 animals (11.3%) of the total number of young animals tested (n=542), which confirms the need to improve the breeding and technological aspects of growing, to carry out careful selection at all stages of sports training and use.

In order to determine the linear affiliation of Belarusian black-and-white breed of boars based on microsatellite analysis, genetic testing was carried out at KSUP Plemzavod Lenino, SGC Vikhra and OJSC SGC Zarechye. 51 alleles were determined according to 9 microsatellite loci in the studied populations. Research data showed that boars with determined “private” alleles at microsatellite loci reliably confirm their linear affiliation and are considered to be successors of the like lines. This gives grounds to consider these alleles as marker for these lines and can be used in breeding and breed formation process.

The paper presents data on assessment of fattening indicators of young pigs of Belarusian meat breed crossed with Landrace pigs, as well as materials of variability of meat and fat traits of cross-bred animals. Thus, the assessment of the main indicators of fattening traits of young pigs of Belarusian meat breed crossed with Landrace pigs showed that the average age of reaching 100 kg of weight made 185.4 days, the average daily weight gain made 738 g, and the feed cost per 1 kg of weight gain made 3.58 feed units, slaughter yield - 68.7%, carcass length - 98.6 cm, backfat thickness - 25.1 mm, loin area - 41.6 cm², hind quarter weight - 11.2 kg. Assessment of variability level of indicators of meat-and-fat traits of animals obtained by crossing sows of Belarusian meat breed with Landrace boars showed there was a need for more stringent selection according to backfat thickness, since variability of this indicator showed the widest range from 6.4 to 18.8%.

Specialists at pig farms in the Republic of Belarus often purchase breeding animals of foreign selection to increase the livestock. Meanwhile, Belarusian pig breeds have obvious competitive advantages over their foreign counterparts, and this factor shall be considered. The perfect parameters of performance of pigs of maternal breeds used in pedigree pig breeding based on selection and genetic techniques and methods are determined. It was established that decrease in reproductive traits with increase in fattening performance is typical of animals of domestic maternal breeds. Criteria for selection of breeding animals of maternal breeds have been developed taking into account their polymorphism according to gene markers of reproductive, fattening and meat traits. The preferred B allele of the ESR gene and the recessive Q allele of the IGF-2 gene should prevail in the maternal line genome. In the paternal lineage genome, the proportion of the preferred Q allele of the IGF-2 gene should be increased in order to improve the fattening and meat traits.

Polymorphism of a number of gene markers of quantitative traits was studied, and it was determined that IGF-2 gene can be used as a marker of fattening and meat performance of Belarusian large white breed of pigs. The frequency of the preferred allele Q is 0.36 decimal quantity, and animals carrying the preferred genotype of the insulin-like growth factor IGF-2^QQ made 24.5% in the studied population of Belarusian large white breed. Studies have shown that the presence of the B allele of estrogen receptor gene in the genome of sows of Belarusian large white breed had a positive effect on multiple pregnancy rate. A significant (p ≤ 0.001) superiority of sows with BB genotype over their coevals with AA genotype was determined: for multiple pregnancy - by 13.4%, number of piglets at weaning - by 11.6%, litter weight at weaning - by 10.1%. Based on the results obtained, schemes have been developed for selection of parental pairs ensuring growth of multiple pregnancy rate by 1-1.5 pigs and growth energy of young animals by 7-9%.

The paper studied correlation of reproductive traits of French and Danish sows with the season of the year during which sow was farrowing, and effect of the sow genotype and seasonal factors on growth of suckling piglets. It was determined that reproductive traits of sows were best among pigs of Danish origin in terms of total number of piglets at birth, multiple pregnancy rate, litter weight at birth, number of piglets and litter weight at weaning compared to animals of French origin. At the same time, sows of French origin exceeded their Danish coevals in such indicators as heavy litter, safety and weight of one piglet at weaning. Evaluation index for a limited number of parameters for comprehensive assessment of reproductive traits showed 16.23% advantage of these indicators in sows of Danish origin compared with animals of French origin. The breeding index of sows’ reproductive traits also indicated that under industrial conditions, the best in terms of complex of traits were Danish pigs, with the index 14.19% higher compared to French pigs. The growth rate of suckling piglets under conditions of an industrial complex was variable during the study period in both groups and varied between the average annual maximums and average annual minimums depending on the current season, increasing in the winter-spring and decreasing in the summer-autumn months. The best growth intensity was shown by French pigs. Variability dynamics of parameters of absolute, daily average and relative weight gain had both smaller amplitude of fluctuations in piglets of French origin under the effect of changes in seasonal environmental parameters, and also superior values compared to pigs of Danish origin were determined. Therefore, the growth rate of piglets of French and Danish origin depends on the genetic affiliation of animals and seasonal factors. The time of the year had a great impact on the growth of piglets during the study period - within the range of 32.63 to 34.95%. At the same time, the genotype had effect on variability of this indicator by 18.23-18.68%, and correlation of these factors - by 7.57-9.01%.

This is for the first time when breeding work has been initiated in the Republic of Belarus to improve the herd of goats producing recombinant human lactoferrin with milk. Genealogical structure of the modern producing herd with 6 lines and 14 families has been studied, and exterior constitutional traits of transgenic animals have been evaluated. Relative uniformity of the studied livestock in terms of exterior and live weight has been determined. Animals had a harmonious constitution, no significant defects and deficiencies were determined.

The paper analyzes the state of horse breeding in Ukraine as a whole and the gene pool of local and small breeds. Characteristics of quantitative composition, scope of horse use, indicators of the main breeding traits and genealogical structure of the Ukrainian riding horse, Novo-Aleksandrovskaya heavy, Hutsul, as well as Ukrainian part of trotter, Trakehner and Thorian breeds are given. Studying breeding composition and horse market of Ukraine in comparison with the advanced countries of equestrian industry made it possible to determine the prospects of horse breeding industry in conditions of increasing the efficiency and stability of functioning in market conditions of enterprises growing horses for equestrian sports and leisure.

The paper presents results of studying the dynamics of hormonal background and peculiarities of prooxidant and antioxidant homeostasis development in pigs during formation of genital function. Significant changes in concentrations of thyroid and steroid hormones with increase in number of estrous cycles have been determined. Intensification of peroxidation processes with estrus phase start was revealed. A generalization of research data indicates one of the features of reproductive function of pigs - appearance of cyclic lability of homeostasis, which is characterized by certain periodic fluctuations. Shift of homeostatic constants during oestrus period is aimed at creating the required conditions for fertilization by method of morphophysiological changes in the reproductive system.

He paper presents the results of studies on indicators of fattening and meat traits of young pigs of large white breed of English and Hungarian origin, level of phenotypic consolidation of these traits, the economic efficiency of the research results has been determined. It has been established that young pigs of white breed of English and Hungarian origin in terms of reaching 100 kg of body weight exceed the minimum requirements of the elite class by age 9.57 by age, and by backfat thickness at the level of the 6-7th thoracic vertebrae - by 28.06 and the length of cooled carcass - by 3.92%. A significant difference between animals of large white breed of English and Hungarian origin has been determined according to average daily weight gain of animals during the control fattening period (0.032 kg), age of reaching 100 kg of body weight (9.5 days) and backfat thickness at the level of 6-7 thoracic vertebrae (2.1 mm). High coefficients of phenotypic consolidation are peculiar for young pigs of English origin in terms of length of chilled carcass (К₁=0.748, К₂=0.833), Hungarian - by the maximum (front) width of the bacon half (К₁=0.465, К₂=0.473). The maximum increase in production was obtained from sale of one young animal of large white breed of English origin (+3.52%), while in animals of Hungarian origin it made 1.91%.

Given the importance of the linear classification technique in determining the breeding value of dairy cattle, the breeding and economic importance of the duration of animals use, studies were conducted in the aspect of determining the correlation of estimation of linear udder traits and longevity of cows. It has been determined that cows with the highest estimates for development of morphological udder traits had a longer life in comparison with animals that have a lower score. Estimation of Ukrainian dairy breeds by the linear classification method confirmed that good development of morphological udder traits was the key to a longer life of cows in the new technological conditions for milk production.

The paper provides statistical analysis of breeding traits of pig population in the Republic of Belarus; population indicators of variability, correlation and heritability of self-performance and reproductive traits have been determined.

The paper presents analysis of viability of cattle embryos after physical treatment of gametes in in vitro technique. Studies have shown that when physical factors directly affected the sire semen, the morphological parameters of semen product improved in in vitro technique prior to capacitation procedure: the percentage of general motility increases, the number of spermatozoa with rectilinear translation motion, number of spermatozoa with developmental anomalies during maturation decreases, which increases the fertilizing ability and survival of gametes in vitro , as a result, increases the number of cleaved oocytes by 22.5-27.5 p.p. and the yield of preimplantation embryos by 8.9-18.8 p.p. relative to the control. Treatment of fertilized oocytes with complex electromagnetic radiation increases the level of transformation of cleaved oocytes into preimplantation embryos by up to 55.6%, which is 27.0 p.p. higher compared to the control. Treatment on gametes of cattle with a complex spectrum of electromagnetic radiation makes it possible to obtain 20.0-20.4% of embryos suitable for transplantation. After treating gametes of cattle with electromagnetic waves, 37.5-41.9% of cleaved embryos reach preimplantation stages and exceed the control index by 8.9-13.3 p.p.

The paper reflects the results of experimental studies of morphological composition of carcasses, cuts of rabbits of meat and meat-and-fell directions of productivity at the age of 120 days, grown using different diets. Small-sized compound feeds with various structure and component ratios were fed to experimental young animals. In the context of three experimental groups, extruded grain components were used; the difference between the groups was to reduce the proportion of extruded barley from 70 to 50% by weight and, accordingly, increase the proportion of soybean grain. The content of hay flour in diets of all the compared groups made 10%. It was determined that French termon rabbits within the weaning period to 120 days of age had rather high growth and development rates compared to rabbits of another breed. They also had higher slaughter and morphological indicators of carcasses, which indicates high ability to intensive growth in comparison with young animals of the Belgian arr breed. It was determined that carcasses contained more muscle tissue at 120 days of age by 16.4% in females and 13.3% in males. The proportion of muscle and fat tissue in general in carcasses increases with age.

Feeding young cattle with extruded lupine grain instead of ground grain had a positive impact on animals performance and contributed to efficiency of productive action of feed. Higher growth energy was observed in experimental group - 920 g of the average daily weight gain, which is 8.3 % higher compared to the control group. As a result, feed costs in one experimental group decreased by 6.65 % and made 6.87 feed units per 1 kg of weight gain. Feed protein cost for weight gain also decreased by 5.6 %. As a result, as well feed costs for weight gain decreased by 7.79 %. Extra profit for the period of production inspection amounted to 23.24 rubles per animal or 1162 rubles for entire livestock.

The the paper presents results of studying the effect of feeding cows with NutriCAB (encapsulated calcium chloride) during the late dry stand period on performance, metabolic disorders and reproductive functions after calving, and zootechnical and economic indicators of such feeding efficiency are also determined. The results of the studies showed that correction of diets during the late dry stand period using NutriCAB product helps to ease calving, reduce the number of metabolic disorders, improve health and reproductive functions of cows, and also ensure stability of lactation.

Our laboratory studies have shown that introduction of “Lactobacillus Metabolism Products” into diet contributes to significant increase in safety of broiler-chickens in experimental groups. The difference in this indicator between the experimental groups made 4.35 p.p., with the control group - 15.8% (group II) and 10.5% (group III). An increase in average body weight was noted as well during the growing period: in group II - by 11.99% (P<0.001), in group III - by 8.7% compared with the control. Introduction of “Lactobacillus metabolism products” into diet for broiler-chickens contributed to reduction of facultatively pathogenic and conditionally pathogenic colonies, which can cause serious diseases in immunodeficient poultry.

Research data is presented with the purpose to determine efficiency of “Bifidobacillus Metabolism Products” when using various doses in diets for Ross-308 cross broiler-chickens. It has been determined that enrichment of diet with this preparation is economically justified, since it contributes to significant increase in safety and average daily weight gain of young animals at the lowest feed cost.

Use of pre- and probiotics promotes improvement of the intestinal balance of microflora in pigs, which contributes to production of healthy young animals and their further intensive growth in conditions of industrial technology. The paper presents materials of the study of efficiency of Lactumin prebiotic in diets for weanling piglets, developed on the basis of whey and representing a composition of natural substances, lactulose and succinic acid. Based on the studies, efficiency of inclusion lactulose-containing prebiotic supplement based on Lactumin milk whey included in SK-16 compound feed in the amount of 1.0%, which helps to significantly increase the live weight of weanling piglets by 4.2% (P <0.05) , daily average weight gain - by 13.8% (P <0.001) and has positive effect on safety of young animals.

Based on the research results, varieties of Belarusian selection were identified with a high yield of green mass (Kovcheg, IZS-2, IZS-3, Zhemchug, Svisloch and Blago 16) and nutritional value (IZS-4, IZS-3, Kovcheg, Yubiley, IZS-2, Zhemchug and Svisloch). These varieties can be used both for grain and green fodder. A high correlation was determined during boot stage between the yield of green mass and the sum of positive temperatures for the period of vegetation resumption to the bump stage (r = 0.61), plant height (r = 0.58) and the number of stems per area unit (r = 0.52). During the flag leaf and heading start stages - between the yield and one stem weight (r = 0.60 and r = 0.56), length (r = 0.54 and r = 0.49) and width (r = 0.51 and r = 0.50) of leaves.

Oilcake obtained by pressing rape seeds cultivated on radioactive contaminated lands of Polissia of Ukraine as a result of the Chernobyl accident contains from 11.17 to 12.43 MJ of metabolizable energy, 311.3 - 336.4 g of crude protein, 88.46 - 148.73 g of crude fat, 113.32 - 121.00 g of crude fiber and 270.34 - 302.16 g, depending on the number of pressing cycles. Its specific activity for¹³⁷Cs and⁹⁰Sr makes 509 and 53.7, respectively, for the first pressing cycle, and 517.0 and 56.0 for the second one. Inclusion of rapeseed cake into diets of dairy cows grown on radioactively contaminated agricultural lands with¹³⁷Cs soil pollution density in the range of 370-555 kBq/m², in the amount of 1.0-1.5 kg practically does not cause any increase in radionuclide contamination of milk. Feeding animals with rapeseed cake increases the average daily natural milk yield by 5.9-8.4% and increases fat content in milk by 2.4-3.2%.

The paper presents results of studying the effect of wet grain preserved using biological and chemical conservant on performance of lactating cows. It has been determined that it ensures production of high-quality feed with metabolic energy of 11.87 MJ, 1.23 of feed units in 1 kg of dry matter. Feeding lactating cows with preserved grain as part of diet helps to obtain the average daily milk yield of 20.2 kg while reducing the cost of diet by 16.4%, which allows to obtain profit of 2.00 rubles per animal per day.

The paper presents results of research with purpose to study the effect of biological and chemical preservative Bioplant-Maxi-2 on quality of preserved food and using them for feeding cows. It has been determined that this preservative used for silage preservation allows one to obtain feed with metabolic energy of 10.08 MJ per 1 kg of dry matter. Inclusion of cereal and bean silage preserved with Bioplant-maxi-2 in diets of lactating cows, allows to obtain the average daily natural milk yield at the level of 19.5 kg, reduce the cost of diets by 1.05% and receive additional profit per 1 animal in the amount of 38.7 rubles.

The effect of compound feeds KR-2 with different levels of oil flax and linen flax cake in diets on hematological parameters of young cattle has been studied during the research. It has been determined that feeding compound feeds with 20% of oil flax and linen flax cake increased red blood cells count by 4.2-8.6%, hemoglobin - by 5.6-13.2%, glucose - by 5.5-6.5% . Increase in level of glucose and fine albumin fraction of proteins combined with 4.6% decrease in urea indicates the diet is balanced according to energy protein nutrition requirements.

The paper presents materials on study of efficiency of introducing Fekord-2015-B dry enzyme feed additive of Belarusian manufacture into diets of laying hens. It has been determined that introduction of Fekord-2012-B enzyme feed additive in diets for laying hens contributes to increase in average egg production by 4.0% (26.0 pcs/hen), egg laying intensity up to 80.6%, while providing egg weight of up to 64.8 g and livestock safety of up to 100%. Food egg was benign according to organoleptic indicators and qualitative characteristics. Profitability of food eggs production increases by 4.5%.

The aim of our research was to determine the growth rate and formation of reproductive function of breeding steers when using various levels of organic form of selenium in diets. It has been determined that use of organic selenium form in the feeding breeding steers in winter and summer periods at the rate of 0.4 mg per 1 kg of dry matter of pure element contributed to increase in average daily weight gain by 6.8 and 7.1%, respectively, and ejaculate volume by 9.5 and 4.5%, spermatozoa activity - by 8.9 and 7.3%, spermatozoa concentration - by 16.4 and 15.7%, spermatozoa count in ejaculate - by 25.0 and 27.3%, spermatozoa fertilizing ability - by 3.6 and 4.1 percentage points and decrease in sperm dose rejection - by 5.0 and 4.6 percentage points.

The paper presents materials of research on dynamics of changes in hematological parameters and study of economic efficiency of Tripoli of “Steel” deposit in Khotimsk district of Mogilev region used in animal feed for highly productive cows. Analysis of the morphological parameters of blood showed that when using mixed feed in diets with tripoli in the amount of 0.5 and 1.0%, a tendency was determined to the increase of concentration of total protein and its albumin fraction, as well as glucose level by 36.4 and 63.6 % (P <0.05). Introduction of tripoli also contributed to increase in concentration of mineral elements in blood during experiment in comparison with the dynamics of the control group, and increase in calcium concentration by 11.5 and 2.9%, phosphorus by 16.3 and 0.3%, and iron by 22 .0 and 20.7%. Feeding of tripoli of “Stalnoye” deposit in Khotimsk district of Mogilev region in compound feeds for highly productive cows contributes to increase in the average daily 3.6% fat milk yield by 1.0-1.1 kg and obtaining of extra products in the amount of 78-85.8 rubles for the experimental period.

The paper presents the results of study of efficiency of the feed additive “Lactumin” used in the diets of lactating cows. According to the data obtained, feed additive “Lactumin” used in compound feeds for highly productive cows in the amount of 0.3, 0.6 and 0.9% or 25, 50 and 75 g per animal per day contributes to extra production of 1.0, 1.2 and 0.9 kg of 3.6% fat milk per cow. The perfect dosage of feed additive “Lactumin” in concentrate portion of diet for highly productive cows is 0.6%, which allows to get additional profit from milk obtained in 96 days in the amount of 79.49 rubles with recoupment of 1 ruble of expense for additive in the amount of 8.7 rubles.

The paper presents the results of study of efficiency of chromium nanoparticles in diets for calves of up to 75 days of age. According to data obtained, chromium nanoparticles in the amount of 0.050 and 0.075 mg per 1 kg of dry matter in diets for young cattle of II and III experimental groups contributes to increase of the average daily weight gain by 6.6-3.3 %, decrease of the cost of production by 4.9-1.4 % and allows to obtain additional profit of 18.0-4.9 rubles per animal, respectively. The method of using chromium nanoparticles (liquid) in feeding young cattle of up to 75 days of age is adding of preparation into milk feeds during daily feeding to each calf.

The results of studies are presented with the aim to study the efficiency of feeding chelate compounds of trace elements of iron, copper, manganese and zinc in various concentrations on performance indicators of pigs during fattening. It has been determined that replacement of balancing zinc compound with a salt form to chelate form and 2 times decrease in concentration had practically no effect on animal performance. Chelate complexes of trace elements are optimal form of compounds of biogenic metals for animal body. Replacing conventional mineral supplement with a chelate supplement of elements allows to significantly reduce their introduction rate into diet and, as a result, reduce concentration in diets.