Research results on usage of DNA-markers (RYRI, FABP, ESRF18/FUTI) and other factors for industrial pork production were presented. It was determined that DNA-technologies let conduct interbreed crossing on industrial scale and get diverse (fat or meat, with different fat content) products, as well as increase pork production in general. The best variants of crossing combinations were pigs of the Belarus large white breed with Belarus meat and Dyurok, and also the Belarus large white breed with Landras and Dyurok. Research results showed, for in course of the whole period of breeding the daily average weight gain of hybrids of the large white with the Belarus meat and breeds Landras was higher than with the Estonian bacon on 25 and 18 g, respectively. Fattening of stores was finished at the period of achievement of body weight by 100-102,5 kg. The slaughter yield of meat products by groups (without intestinal fat) did not essentially differ and varied within 69,9 - 71,1%. There were noted no considerable distinctions in weight of internals (heart, lungs, kidneys, spleen, liver). Thickness of the salted pork fat at hybrids with animals of the Belarus meat breed was 1-2 mm lower than in other. The average meat yield of diverting weir was 61,9%, fat weight - 27,9%, bone weight - 10,2%. The organoleptic evaluation of beef-infusion broth quality showed that indicators of habit, aroma and taste and nourishing were at high level and compose 4,67; 4,59; 4,55 and 4,71 points, respectively. Tenderness, juiciness and taste of boiled meat also were at level 4,69; 4,76 and 4,87 points, respectively; fried meat - 4,57; 4,68 and 4,66 points

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

In the research the genetic structure of populations of bulls Vitebsk of cattle breeding state farm and cows of Belarusian Black-and-White breed of Joint-Stock Company Olgovskij of Vitebsk region (Republic of Belarus) on a locus of a gene of kappa-casein was analyzed. As a result of genotyping a gene of kappa-casein by DNA-diagnostics method there were revealed three genotypes CSN3**AA, CSN3**AB, CSN3**BB. Frequency of occurrence of homozygous genotype CSN3**AA at cows has made 69,5%, at bulls of Vitebsk cattle breeding state farm - 78,3%; heterozygotic genotype CSN3**AB - 26,3% and 20,5%; homozygous genotype CSN3**BB - 4,2% and 1,2%, respectively. Frequency of CSN3**A allele in population of cows and bulls has made 0,83 and 0,88; CSN3**B - 0,17 and 0,11%, respectively. The presence of authentic influence of polymorphic variants of a gene of kappa-casein on level of milk yield and fat and protein content in cow milk was stated. The highest milk productivity in course of 305 days of lactation was observed at cows with homozygous genotype CSN3**BB (5984 kg), that was on 890 kg higher than in animals with genotype CSN3**AB (5094 kg), and on 1406 kg higher (Р less than 0,05), than at animals with CSN3**AA genotype (4578 kg). Cows with B kappa-casein allele in genome were characterized by higher fat content in milk (CSN3**AB - 3,61%, CSN3**BB - 3,72%) than animals with a CSN3**AA genotype - 3,60%. Cows with genotype CSN3**BB had higher level of protein in milk (3,28%) in comparison with the animals with CSN3**AA genotype (3,18%). In animals with CSN3**AB genotype the mentioned above index 3,19%. Research results showed that genetic variants of the gene of kappa-casein are important for selection practice as they could be used as breeding-genetic markers which could raise milk yields and protein content in milk