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

Improvement of the standards of energy and protein diets of young stock cattle of 1-6 month old and determination of its influence on animal productivity was realized in the conditions of the Republic of Belarus. The studied made it possible to determine that at the age of 1 month the calf diet should contain 1,02 kg of dry matter and 21,2 MJ of metabolic energy; at the age of 2 months - 1,26 kg and 23,5 MJ; at the age of 3 months - 2,2 kg and 25,6 MJ; at the age of 4 months - 2,9 kg and 31 MJ; at the age of 5 months - 3,28 kg and 34,2 MJ; at the age of 6 months - 3,76 kg and 37,6 MJ, respectively. Metabolic energy concentration per 1 kg of dry matter should not be lower than 20,7 MJ at the first month, 19 MJ - at the second month, after the third month it should lower up to 10 MJ. In course of 6 months the presented diet scheme made it possible get 832 g of average weight gain in the conditions of forage expenses of 3,52 forage units per 1 kg

The immune status of chickens, pigs and calves depends on the content of protective factors in incubatory egg, mother colostrum and timely transfer to their posterity. At young growth in postnatal ontogenesis it is allocated three age immune deficiencies. The first is connected with untimely receipt transovarian and colostoral factors of the protection, the second is caused by an expenditure of passively transferred protective factors of protection and immaturity of own immune system. The third age immune deficiency arises at sharp transfer of young growth into new type of feeding and concerns, first of all, disorders of local protection of a digestive path. Timely application the probiotic enterobifidin, baktril-2, bifidoflorin, developed by Vitebsk State Academy of Veterinary Medicine together with Institute of microbiology of the National Academy of Sciences of Belarus, microbic polysaccharides salmopul and vistimulin, received together with Vitebsk biofactory, and also diamiksan allows to prevent development of immune deficiencies and on their background gastroenteric and respiratory diseases of young growth, to stimulate animal growth and to improve quality of meat production, decrease economic efficiency and ecological safety, considerably allows to reduce application of antimicrobic preparations (antibiotics, Sulfanilamidum, Nitrofuranums, etc.) | Иммунный статус цыплят, поросят и телят зависит от содержания защитных факторов в инкубационном яйце, молозиве матерей и своевременной передаче их потомству. У молодняка в постнатальном онтогенезе выделяется три возрастных иммунных дефицита. Первый связан с несвоевременным поступлением трансовариальных и колостральных факторов защиты, второй обусловлен расходованием пассивно перенесенных защитных факторов защиты и незрелостью собственной иммунной системы. Третий возрастной иммунный дефицит возникает при резком переводе молодняка на новый тип кормления и касается, прежде всего, нарушения местной защиты пищеварительного тракта. Своевременное применение пробиотиков энтеробифидина, бактрила-2, бифидофлорина, разработанных Витебской государственной академией ветеринарной медицины совместно с Институтом микробиологии НАН Беларуси, сальмопула и витстимулина, совместно полученных с Витебской биофабрикой микробных полисахаридов, а также диамиксана позволяет профилактировать развитие иммунных дефицитов и возникающих на их фоне желудочно-кишечных и респираторных болезней молодняка, стимулировать рост животных и улучшать качество мясной продукции, повышать экономическую эффективность и экологическую безопасность, значительно сократить применение противомикробных препаратов (антибиотиков, сульфаниламидов, нитрофуранов и др.)

There was studied the width of distribution and peculiarity of clinical manifestation of mineral exchange diseases at pregnant sows, and also perfection of preventive actions at pathology of mineral metabolism in the conditions of prophylactic medical examination. Results of research have shown, that diseases of mineral metabolism widespread (84,7%) among pregnant sows in the conditions of industrial production, are most extended scarce conditions on Zn (17,7%) and Fe (22,5%). Clinically this insufficiency was expressed by oppression, appetite distortion, occurrence on a skin of specifically red stains correct roundish the form: with the clarified sites in the centre, are registered as abortions at final stages of pregnancy. It is established, that the way of preventive maintenance of hypomicroelementosis of pregnant sows with use of chelated forms of microelements is more preferable than sows, as reduces percent of clinical display of Zn and Fe deficiency, stabilize level of hematological and biochemical indicators of blood more effectively, and also raise industrial indicators of pregnant sows. | Целью работы было изучение широты распространения и особенностей клинического проявления заболеваний минерального обмена у супоросных свиноматок, а также совершенствование профилактических мероприятий при патологии минерального обмена веществ в условиях диспансеризации. Результаты исследований показали, что болезни минерального обмена веществ широко распространены (84,7%) среди супоросных свино¬маток в условиях промышленного производства, наиболее распространены дефицитные состояния по Zn (17,7%) и Fe (22,5%). Клинически эта сочетанная недостаточность выражалась угнетением, залеживанием, понижением и извращением аппетита, появлением на коже специфически красных пятен правильной округлой форма: с просветленными участками в центре, зарегистрированы так же аборты на конечных стадиях супоросности. Установлено, что способ профилактики гипомикроэлементозов супоросных свиноматок с использованием хелатных форм микроэлементов предпочтительнее, поскольку сокращает процент клинического проявления дефицита цинка и железа, эффективнее стабилизируют уровень гематологических и биохимических показателей крови, а также повышают производственные показатели супоросных свиноматок.

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

Application of ethologic techniques in commercial swine production made it possible to take into account the specific features of pigs, to separate animals suitable and unsuitable for animal husbandry in the conditions of industrial production technology, as well as to solve many other problems connected with management, animal behaviour at farms and complexes, that could make it possible to obtain additional production without investing additional material resources. The behavioural trait of emotional stress resistance rendered the authentic positive impact on growth rate of piglets during the suckling period. Taking into consideration, that emotional stress resistance, as well as the temperament as a whole, remained invariable as long as life endures, it could be possible to recommended to use the analysed trait for the selection of young stock for self- replacement in the conditions of pig-breeding complexes, and for the selection of the most fast-growing animals with the simultaneous steady resistance to the emotional stress. In the process of replacement pigs selection it was inefficient to take into consideration only their live weight. Considering that the live weight of some piglets which were non-resistant to emotional stress, but with heavy litter, was high enough, however, as their temperament did not vary as long as life endures and emotional instability will necessarily manifest itself in the subsequent parent qualities of the future sows

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

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

The purpose of research is to study influence of fodder additive Water Trit liquid on dynamics of live weight, natural resistance and determination of an optimal dose for pigs on growing. Thanks to рН decrease of intestines contents and presence of organic acids the additive is applied for disease prevention. Presence of organic acids stimulates the development of useful Lactobacillus micro flora in intestines gleam. From the received data positive influence of the fodder additive on a gain of body weight is visible. In the beginning of experiment the difference in body weight of a control and a trial groups was insignificant and made from 9,2 kg to 9,4 kg in the experimental group, and 9,3 kg - in the control group. In the end of experiment the difference in body weight was essential: 28,6 kg, 30,5 kg, 29,5 kg in the trial groups and 28,05 kg in the control. After application of the fodder additive Water Trit liquid in the trial groups there were noted the raised daily average weight gains: on 2,6% in the second, on 13,4% (P less than 0,05) - in the third and on 8,5% - in the fourth group in relation to control group. For studying of the influence of the fodder additive on animal organism there was carried out the blood testing: phagocytosis, bactericidal activity of blood serum, lysozyme activity of blood serum. Indexes on phagocytal index at animal of the control and trial groups were in the beginning of experiment approximately at one level. At 45-day age the indexes in the second and fourth trial groups were above the control ones on 5,2% and 8,9%, respectively. By the end of the experiment the phagocytal index in all four groups changed insignificantly. At studying of lysozyme activity of blood serum at pigs the given research have shown, that at 30-day age the indexes in the third and fourth trial groups were above the control, and indexes in the first group were above the standard of the control. At 70-day age the highest lysozyme activity of blood serum was in the second trial group and has made +16,0% to the control. It is necessary to notice, that on the 70th day this indicator was above the control in all three trial groups