Determination of the optimum parameters of cattle embryos production in vitro from high-producing cows after their slaughter on a meat-packing plant was realized in the conditions of the Republic of Belarus. Oocyte cumulus complexes of cows of black-motley breed and the conditions of their maturing were used as the object of experimental research. Oocyte cumulus complex were allocated with dissection of ovaries tissue placed into Hanks culture medium. The search and morphological estimation of quality of received oocyte cumulus complexes were realized by microscopic research. Then, the oocytes were placed into a culture medium for cell maturing in СО2-incubator at 38,5 deg C with the maximum humidity (98%), with presence of 5% СО2 under a layer of mineral oil for 24 hours. Matured oocytes were impregnated with the frozen-thawed sperm after capacitation. Oogenesis efficiency of production of pre-implantation germs in vitro was determined in accordance with the level of embryonic fission and production of viable germs. Use cumulus cells monolayer made it possible to increase the quantity of ripened oocytes on 5,2-5,7%, level of embryonic fission - on 14,0-14,6% and production of embryos - on 13,8-12,5% depending on a way of its production in comparison with groups of the cells which were cultivated without a monolayer. Thus, the research has shown the exploitability of use of cellular reproductive technologies in selection and breeding activities in cattle breeding. Their application in combination with embryo transplantation could make it possible to use the reproductive potential of high-priced oocyte donors more effectively for the genetic improvement of animal population efficiency

As a result of the realized in the conditions of the Republic of Belarus research on revealing the influence of polymorphism character and the influence of presence of various allelomorphic variants of IGF-2 gene in breeding boars genotype on fattening and carcass traits of stores of Belarusian large white and Belarusian meat breeds it was established: 1. frequency of occurrence of desired QQ genotype among boars of the Belarusian meat breed was rather low and has made 10%. Among boars of the Belarus large white breed the given genotype has not been revealed. Heterozygotic genotype Qq had a rather wide range - from 26,6% at boars of the Belarusian meat breed to 43,2% at boars of the Belarusian large white breed; 2. fattening boars of both studied breeds which had been received from the boars bearing in their genome Qq genotypes of IGF-2gene showed the tendency for predominance in fattening and carcass traits over their herdmates which had been received from the boars bearing in their genome qq genotypes; 3. The posterity of boars of the Belarusian meat breed bearing in their genome the homozygous QQ genotype, authentically surpassed in fattening and carcass traits their analogues which had been obtained from fathers with a genotype qq. The following traits were higher: age of achievement of body weight; daily average weight gain in case of fattening; feed expenses per unit of live weight gain; slaughter yield; weight of a back third of half carcass. Research results showed, that IGF2gene (a gene of the insulin-like growth factor) could be a perspective candidate gene which makes it possible to predict the growing capacity and carcass trait of pigs of Belarusian breeds. Taking into consideration the influence undesired q allele, for the increasing of fattening and carcass traits of pigs it was possible to recommend the realization of estimation of replacement boar pigs using the data analysis of their genotype of IGF2 gene, as additional criterion of their selection

In the pig enterprises of Belarus the most widespread sources of heat for pigs heating proved to be the infrared radiation lamps. In recent years there was stated the wide application of electric heated rugs of various designs or the electric heated floors. The special brooders, equipped with various sources of heat, passed the experimental check possibility of use for heating of pig houses. Their advantage was in decreasing of heat losses in the sleeping areas of pigs that demanded lower expenses of energy for heating of stores. However, till the present the effective brooder design, which could be convenient in use, cheap, easily sanitized and providing an optimum microclimate for piglets, was not offered for the production yet. Agricultural enterprise Kadehks has developed a design and the pre-production model of a warmed den for pigs under the name Logovo Dlya Porosyat UKhL-4 (Logovo). Application of brooder Logovo in combination with the warming plate made it possible to design more favorable mode for sleeping areas of pigs, to reduce preheating time of plates up to 10 days, to save (in comparison with incandescent lamps) up to 155 kw/h of electric power used for heating of pig sleeping area without decreasing their growth rate and safety. Application of the presented device in combination with heating plates made it possible to reduce the expenses for pig production and for the equipment of heating plates temperature regulators. Application of the differentiated heating mode with the possibility to deactivate the heating plates from the electric power sources after 10 days of the suckling period made it possible to lower the expenses for production of female socket of pigs

Beef production in the Republic of Belarus could be competitive only in case of development of the specialized beef cattle breeding. Therefore, for the increasing of beef production and improvement of its quality in Belarus there was noted the necessity to use cattle beef breeds both in case of straightbred breeding, and in crossing with low income-earning Black-and-White cow stock. Research results showed that hybrid Gereford x Black-and-White breeds of the first and second filial generations showed higher reproductive abilities which were manifested in 105-120 days age reduction at the stage of the first insemination, 18-44 days reduction of service period, 0,07-0,1 times increasing of breeding efficiency index, 9,8-14,4% increasing of calf crop per 100 dams, and 14,4-16,4% increasing of young stock livability in comparison with the Black-and-White breeds calves. Research results showed that the non-heating season of the mongrel Gereford x Black-and-White heifer breeds of the first and second filial generations was 396-400 days, breeding efficiency index (rate of fertilization) - 1,29-1,32, breeding performance index - 85,4-90,0%, while for the at Black-and-White heifer breeds the same indices were 425 days, 1,29 and 75,6%, respectively

The growth and development of replacement gilts of different precocity and age depending on the terms of transition from herd-producer to the market area of a complex was studied in the conditions of the Republic of Belarus. Animal transfer into new housing conditions affected the early maturing and super early maturing breed pigs of experimental groups. It was determined that moving of replacement pigs into the market area of the complex at the age of 115 days made it possible to obtain higher indices of swine productivity. Fertilization rate of sows of the first experimental group after the first insemination made up 77,6%, that was higher on 6,2% and 9,5% in comparison with the control and the second experimental groups, respectively. The advantage of the first and second experimental groups over the control one was stated in a higher multiple fetation on 0,4 heads and heightened heavy litter indices on 0,1 kg; the quantity of weanling was higher on 0,6 and 0,5 heads, on litter weight at weaning was higher on 7,1 and 3,8 kg, respectively

Belarus is among regions, where the selenium content in soil, hence, in cereal and other cultures considerably below requirements that leads to insufficiency of this microelements in a diet as the person, and animals. Synthesized in the All-Russian Scientific Research Institute of Physiology, Biochemistry and Feeding of Agricultural Animals new organic compound of selenium - selenopyran on variety of criteria has no analogues in the world among considerable quantity selenium of containing preparations and favourably differs from all known forms of microelements. Selenopyran, brought in fats and forages, shows antioxidatic the properties which are not conceding traditionally applied in veterinary science and medicine to antioxidants. Arriving in animal body with forage or in the form of injections, selenopyran is capable to play a role of a metabolic regulator. It activates enzymes of antioxidatic body protection, reduces formation new and will neutralize of earlier formed activeproducts of peroxide lipids oxidations, improves functioning of cellular membranes, normalizes metabolism, makes active cellular, humoral and phagocytal immunity links, raises nonspecific resistance and efficiency of animals. Toxicity of selenopyran more low, than at all known organic connections of selenium, and more than in 100 times is less, than at sodium selenit. The data allow to expand possibilities of application of organic selenium and to use it as a preparation raising resistance and body viability at the expense of the patronage of cellular structures from influence of oxidizers and free radicals, to normalize metabolism and to stimulate thus the big additional body weight at animals. The influence of medicine organic selenium on piglet bodies what are behind a growth and development is shown. The results showing the dynamical changes of haematologicals, physiologicals and biochemicals indices under the influence of selenopyran was given.

The use of low intensive red spectrum laser radiation for prevention of abomasoenteritis in calves is effective method. As a result the increase of erythrocytes level and saturation of them with hemoglobin happens. Natural resistance with bactericide and lysozyme activity are going up phagocytosis of neutrophils is activated. The most successful method are magnet-laser radiation of blood and laser acupuncture. There was studied the low intensive red spectrum laser radiation for prevention of abomasoenteritis in calves. During the research it is established, that preventive efficiency at abomasoenteritis in the first trial group has made 80%, in the second and the third - 90%. As a result of the spent work high preventive efficiency of action of the low intensive red spectrum laser radiation is established at prescription of through-skin blood irradiations by the therapeutic laser in a combination to a constant magnetic field and as a result influences on biologically active points. Application of these ways allows to reduce level of disease of animal abomasoenteritis. As a result of physiotherapeutic influence there is content increase of erythrocytes in blood of calves and saturation their haemoglobin. Natural resistance with bactericide and lysozyme activity are going up phagocytosis of neutrophils is activated. The most successful method are magnet-laser radiation of blood and laser acupuncture. It is caused by that positive changes occurring in an organism, have been more brightly expressed and besides preventive and economic efficiency of these ways of irradiation also were at higher level. In the tabular form dynamics of morphological indicators at calves under the influence of laser radiation, dynamics of indicators of natural resistance at calves as a result of the laser therapy, some biochemical indicators of blood is presented at carrying out of research.

There was studied the therapeutic efficiency of sorbent Lactofiltrum in a complex therapy of abomasoenteritis at calves. It represents the complex preparation containing 75% of hydrolytic lignins and 25% of lactulose. Action of lignins is based on ability to sorb and strongly to keep toxins of exogenous and endogenous origins, the pathogenic microorganisms which are present in enteral mediuim. Lactulose, a part of prebiotics Lactofiltrum, is a synthetic disaccharide. It is not exposed to splitting by enzymes in thin intestines. The active substance lactulose starts to operate in a thick gut where under the influence of intestinal microflora it is transformedto low-molecular organic acids, basically dairy, acetic, oil and propionic. Thanks to acidification of intestinal contents growth of putrefactive and pathogenic microflora chokes, osmotic pressure in a gleam of a thick gut increases. Lactofiltrum possesses high therapeutic efficiency. The experiment has shown 100% effectiveness in treatment. Economic effect is 1,63 rubles in control group and 3,52 rubles in experimental group from 1 ruble of expenditure. This treatment is economically profitable. In the tabular form the content of the general bilirubin, cholesterol, triglycerides and glucose in blood serum, urea and creatinine, daily average body weight gain and epizooty, morphological indicators of blood, dynamics of the general protein and albumens at calves with abomasoenteritis are presented. Lactofiltrum has a high therapeutic effect. Pharmacology action is associated with intestinal digestion normalization due to absorption of toxins and useful bacteria stimulation. The experiment has shown 100% effectiveness in treatment. This treatment is economically profitable.

In course of realized in the conditions of the Republic of Belarus research there were studied the relations of the most widely spread helminthes and protozoan which infest in gastrointestinal tract of dogs with the normal microflora of small intestine and large intestine. Research results showed that in the conditions of single-agent infestation and associative parasitic disease of dogs caused by Toxocara canis, Toxascaris leonine, Dipylidium caninum, Uncinaria stenocephala, Taenia sp., Isospora ochioensis, Isospora canis and Eimeria canis in small and large intestine of sick animals there was seldom stated the changes of quality and quantity composition of microflora. In the conditions of mixed agents infestation the microflora composition changed more intensively

The organizational aspects of reproduction in a swine heard were featured, the productivity indices of the crossbred sows obtained through the crisscrossing of the Belarusian Large White, Belarusian Black and White and Estonian Bacon pig breeds were given. The duration of the gestation period for the sows of different origin was shown. The results of the realized experiment showed that at all stages of reproduction there was required the full-value feeding and the maintenance of animals, observance of terms of revealing of sexual hunting and timely insemination of sow. For the systematic increase of swine productivity for selection of replacement pigs for reproduction besides the standard indicators it was necessary to consider the duration of gestation period. In course of study there was stated the well-defined consistent pattern of increasing of pig average weight which were born from sows with the lengthened gestation period. Piglets with the standard and extended term of prenatal growth showed higher indices of body weight at a birth and surpassed their herd mates with the shortened duration of prenatal development on 8,6-10,5% (Р less 0,001). Heavy litter of pigs affected the intensity of their subsequent development. At the weaning stage the weight of 1 pig with the shortened prenatal development was 6,25 kg, and the weight of pigs with the standard and extended periods - 6,62 kg (Р less 0,001) and 6,89 kg (Р less 0,001), respectively and exceeded on 5,9% and 10,2%. The 3-month age pigs with the shortened prenatal development lag behind herd mates with the standard and extended period of prenatal development in the indices of growing capacity on 1,2-1,4 kg (4,0-4,6%). The same tendency was noted after fattening period