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

For the first time in the Republic of Belarus there were developed the effective methods of marker-dependent selections directed towards increasing the performance traits and preventive measures of pig diseases of the Belarusian Large White breeds. Application of the presented techniques in practice made it possible to increase the multiple fetation of sows on 0,5-1,5 piglets, increase livability of stores on 1,1-5,7%, increase the average daily weight gain on 17g, lower feed expenses on 0,04 FU. In course of the realized studies there was studied the polymorphism of Ryr-1, ESR, E.Coli (ECR F 18) FUT 1 and IGF-2 genes, there was developed the efficient methods of marker-dependent selection. Research results showed that application of methods of molecular gene diagnostics proved to be economically feasible. In the conditions of rather low expenses for testing of boars and sows there was stated the considerable increases in economic efficiency of pork production. Creation of reserve populations with a desired genotype breed will make it possible to accelerate the breed-forming process

Determination of the optimal doses of selenium inclusion into premix structure for breeding boars for the maintenance of their higher producing capacity was realized in the conditions of the Republic of Belarus. Selenium lack in boar rations caused the degenerative changes in seminal glands, low male germ cells concentration and lowering of spermatozoon motility, which subsequently decreased their producing efficiency. Research showed, that selenium inclusion in premix KS-1 structure in quantity of 30 mg per 1 kg in comparison with premix in 20 mg dose have improved the yielding productivity of mature boars: the average quantity of male germ cells per one ejaculate increased on 17,2%, the average quantity of born pigs from per one sow increased on 4,8%. The additional profit per one boar was on 6,06% higher than in control experiment

The increasing number of diseases with urogenital chlamydiosis became a serious problem for the modern veterinary science. The importance of urogenital clamidiosis in the infectious pathology of animals was presented by the direct multifocal affect of urogenital system and after-effects of a disease influencing the reproductive function, as well as the potential hazard of its transformation into a source of chlamydia infections of other localization. In the conditions of the Republic of Belarus the chlamydial endometritis of cattle in the majority of cases was associated with Staphylococcus aureus in 25,7% of cows. Chlamydial endometritis of cows was usually preceded by: embryotocia (9,9%), pathological calving (4,4%), retention of placenta (14,8%), subinvolution of uterus (27,1%). The biochemical tests in trial group showed the 23% decrease of carotin on twofold decrease vitamin A. In course of the immunologic studies it was established, that dilution of A class immunoglobulins was on 31% higher in animals of a trial group in comparison with the control group. The level of IgG immunoglobulin G and immunoglobulin M slightly differed between groups

Development of a new method of boar evaluation taking into account their beef-making and fattening qualities as well as their posterity viability for the further selection of the best ones and for the culling and ranking of the worst ones was realized in the conditions of a large pig-breeding complex of the Republic of Belarus. Scientific and economic experiment was realized at the JSC Sozh, Gomel region (Belarus) at the pig-breeding complex with 108 thousand livestock heads of annual fattening. At a finishing stage of sow hybridization the combinations of Large White х Landrace and Large White х the Belarusian Meaty breeds were inseminates by boars of 990 synthetic lines (N11151 and N11146), the Belarusian Meaty breed (N3495), Landraces of the Polish (N40, N37, N78) and German selection (N11262, N11263, N11266), and also by a hybrid boar of 990 lines х Petren (N11145). Sow insemination was realized in three technological groups. Sows were selected taking into account their breed, age and last productive ability in order to avoid inbreeding. At the same time, each boar was checked up on the breeding stock for identical quality. The final estimation of boars was stated at the stage of achievement by their posterity of selling weight (before sending to a meat processing plant). The offered method made it possible to get an objective comparative estimation of breeding characteristics of tested boars in the conditions of a complex

In the process of monogastric animal feeding, including pigs, the special role is played by the quality of coarse grain crops as they compose 70-75% of swine ration structure. Determination of fodder productive effect on fattening swine was realized in the conditions of the Republic of Belarus. The basis of the analyzed fodder was formed by fodder grain of extra fine grade. Research results showed the following: inclusion of extra fine grade barley (Hordeum vulgare) and wheat (Triticum aestivum) (chosen in accordance with the standard of the Republic of Belarus) into all-in-one mixed fodders SK-26 and SK-31 for fattening swine made it possible to obtain higher productive capacity of the experimental animals in comparison with the identical mixed fodders containing barley and wheat of other grades (chosen in accordance with All-Union State Standard 28672-90); in the experimental groups the average daily weight gain in course of the fattening period was on 34 grams higher, and the average selling weight of 1 head - on 4,1 kg than in the control group. Swine which were fed with the presented mixed fodders with grain extra fine grade showed fewer deviations from the rated value of metabolism (blood serum protein and its fractions, calcium, phosphorus, acid capacity) in comparison with the control groups

Research of the selection efficiency of boars of Belarusian meaty and Large White breeds for reproduction and productivity indices was realized in the selection and breeding centre Zadneprovski in the Republic of Belarus. The influence of 25-percentage level of boar selection for sperm production with the dominancy of relative average values of an initial population on statistically significant difference within the limits P less than 0,05-0,001 was proved. Application of an evaluation criterion of animal breeding abilities by the degree of frequency of departures from a population level with a value which reflects the intensity of selection in shares of an average quadratic deviation made it possible to raise the breeding value of boar of both genotypes in accordance with the productive qualities of descendants in comparison with average sizes of populations of two breeds on statistically authentic difference at P less than 0,05-0,001. Decreasing in the studied indicators of efficiency of offsprings concerning initial fatherly forms could be explained by a stronger influence of environment conditions rather than genetic predisposition of genotypes to the given traits

Research of possibility of application of sapropel (putrid mud) of the Chervonnoe lake (the Republic of Belarus) in diets of bred and milking sows as one of the ingredients of mixed fodders, as well as the evaluation of its influence of sow development and digestibility of nutritive elements were studied. Application of dry sapropel a source of energy, protein, mineral and vitamin nutritive elements for mixed fodder production rendered the positive influence on sows productive qualities: there was stated the increased number of born piglets on o,5 heads with a higher growing capacity; there was noted the increasing of coefficients of nutritive elements metabolism (crude protein – on 2,7%, crude fat – on 2,9%, free-nitrogen extracts – on 1,3%, and dietary fibre – jn 4,7%) with the simultaneous increasing of nitrogen, calcium, and phosphorous uptake by sows. Nutritional value of the analysed sapropel was 0,23 fodder units and 3,13 MJ of exchange energy per 1 kg of dry matter. Inclusion of 3% sapropel into mixed fodders for pregnant and suckling sows promoted the increasing of quantity of pigs at a birth, body weight of one pig to 3-week age and has ensured young growth with higher energy of growth. Use of sapropel in mixed fodders for sows makes active a metabolism and promotes increase of digestibility of the basic nutrients of a rations

Study of the regeneration processes and raising the efficiency of rape (Brassica napus) organs and tissues cultivation in vitro methods, as well as the achievement of a stable yield of proper regenerants were realized in the conditions of the Republic of Belarus. The obtained data specified the possibility of generation of rape finished regenerants in vitro culture without additional passages and transfers by means of effectively selected concentrations of phytohormones and biologically active substances, which made it possible to realize principles of totipotency and polarity of crop vegetative organs. On the explant part which was submerged into culture medium there was formed a root, and on opposite one - the morphogen structures. The possibility of obtaining rape regenerants from hypocotyls segments by straight regeneration was studied. Application of the analyzed substances considerably simplified and reduced the price of process of full regenerants formation, and made it possible to receive a wide spectrum of various forms that was important for selection process due to the opportunity to select valuable (in protein content) samples for the further studies and their inclusion into production process