Research on preserving ability of the biological preserving agent Bioplant for grass and maize silage making was realized in the conditions of the Republic of Belarus. Application of Bioplant in course of grasess and maize encilaging promoted the faster accumulation of the significant amount of milk acid and decreasing of рН up to 4,1-4,2. Silage which was prepared with preserving agent Bioplant corresponded to the top grade of quality. Application of Bioplant for preparation of siloed forages promoted the reduction of losses at their storage. For example, in grass-legume and cereal silage there was a reduction of dry matter losses in comparison with control silage - on 4,7 and 4,2%, crude protein - on 5,6 and 5,0%, respectively. In maize silage the addition of the preserving agent there was stated the decreasing of nutrient losses in comparison with the control: dry matter - on 5,2%, crude protein - on 6,2%. Feeding of wedder hogs with the silage preserved by the preserving agent Bioplant provided higher digestibility of crude protein in comparison with the control group: on 3,2% in the conditions of grass-legume silage use, on 2,4% - in the conditions of feeding with cereals, and on 2,9% - in the conditions of feeding with maize silage

Nowadays in connection with an interdiction for antibiotics use in animal feeding it is very actual to work out and apply new forms of probiotic preparations which should be as ecologically safe and harmless both to people and animal products. Probiotics make it possible to improve the digestibility of nutritive substances of forages, normalize metabolism, enrich with biologically active substances that promotes the increasing of their productivity. In the Republic of Belarus the probiotics are produced in the obviously insufficient quantity that creates problems of young stock livability. Influence of application of Akozil and Sublicin probiotics in diets of suckling calves on biochemical parameters of blood serum was analysed. It was stated that use of the analysed probiotics made it possible to decrease the level of urea and total cholesterol, to increase of the total protein content in blood serum of the experimental calves. There was noted the increasing of glucose level in blood serum of calves fed with Akozil. There was marked the tendency of more optimal level of calcium and phosphorus in calves having Sublicin in their diets. The obtained results testified the normalization of metabolic processes taking place in calves which were fed by the mentioned above probiotics

In process of animal husbandry intensification much attention should be given to maintenance of the high-grade balanced feed of animals. Forage supplement Profat (Protected Fat) is a protected fat in dry-sand mould with 84% of fat content. Application of 0,5-0,8 kg of dry fat supplement in cows diets per 1 head a day (4,7-10,0% in mixed forage content) promotes the increasing of prime cost of milk yield with basic fatness at 1,8-2,8% within fatness growth at 0,1-0,24% without protein content decrease. During the analysis of morphological and biochemical blood structure there was not established any considerable inter-group distinctions. At the same time, it is necessary to notice, that in blood of animals of two experimental groups there was stated a little bit higher protein content. However, in proportion to application of experimental fat additive up to 0,8 kg per head a day the protein content decreased. The increased number of erythrocytes and hemoglobin content in blood of animal of trial groups proved the strengthening of metabolic processes. In blood of trial groups it was noted high quantity of vitamin A and phosphorus as well as lower amount of calcium

Appraisement of new mixed fodder formulas for the fattening performance test was realized in the conditions of the Republic of Belarus by the example prevailing in the country Large White breed. Barley (Hordeum vulgare) proved to be one of the main components in swine feeding in Belarus. Forage wheat in mixed fodders for the fattening performance served a basic energy source and contained less dietary fibre than barley, as well as less concentration of antinutrients which interfere with digestion of rations than others crops (rye, triticale). Soybean and sunflower oil meal were included into analysed mixed fodders as the protein sources. Application of new mixed fodder formulas for fattening control realization according to the technical specifications of the Republic of Belarus 600039106.044 - 2007 was realized by the example of gilts of pigs of Large White breed. Research results showed that new studied formulas made it possible to obtain the higher intensity of swine development indices (on 52-72 grams) in comparison with the traditional formulas of mixed fodders (technical specifications of the Republic of Belarus 06093149.065-2000). New mixed fodder recipes did not render harmful effect on health and safety of livestock. At the same time, the analysed recipes of mixed fodders did not authentically influence the carcass indicators (carcass length, fat thickness, loin eye area, ham weight, slaughter yield)

There was studied the activity of alaninaminotransferase and aspartataminotransferase, alkaline phosphatase, gamma-glutamiltranspeptidase, lactate dehydrogenase, cholinesterase, alpha amylase in blood serum, liver and pancreas of replacement young hens. At carrying out of immunization of replacement young hens by a vaccine against infectious laryngotracheitis, developed in Institute of experimental veterinary science, reaction from the party not only bodies of immune system, but also such bodies, as liver and pancreas, takes place. Biochemical reaction of the specified bodies to immunization is a consequence of adaptability of an organism to vaccinal stress. Biochemical changes of display enzymes in blood serum, pancreas and liver are found out. It was marked increase of activity of the given enzymes in liver, pancreas and blood serum so, activity of alaninaminotransferase and aspartataminotransferase, alkaline phosphatase, gamma-glutamiltranspeptidase, lactate dehydrogenase increased at birds of trial group in 1,3-1,9 times in comparison with the control. In the tabular form data on activity of alaninaminotransferase, aspartataminotransferase, alkaline phosphatase in liver, pancreas and blood serum of repair young growth of the hens vaccinated against infectious laryngotracheitis are presented. | Целью наших исследований явилось изучение активности аланин- и аспартатаминотрансфераз, щелочной фосфатазы, гамма-глутамилтрансферазы. лактатдегидрогеназы, холинэстеразы, альфа-амилазы, в сыворотке крови, печени и поджелудочной железе ремонтного молодняка кур. При проведении иммунизации ремонтного молодняка кур вакциной против инфекционного ларинготрахеита, разработанной в Институте экспериментальной ветеринарии им. С.Н. Вышелесского НАН РБ имеет место реакция со стороны не только органов иммунной системы, но и таких органов, как печень и поджелудочная железа. Биохимическая реакция указанных органов на иммунизацию является следствием адаптивности организма к вакцинному стрессу. Выяснены биохимические изменения индикаторных ферментов в сыворотке крови, поджелудочной железе и печени. Отмечалось сочетанное повышение активности данных ферментов в печени, поджелудочной железе и сыворотке крови, так, активность АлТ, АсТ, ЩФ, ЛДГ, ГГТФ повышалась у птиц опытной группы в 1,3-1,9 раза по сравнению с контролем. В табличной форме представлены данные по активности аланинаминотрансферазы (АлТ), аспартатаминотрансферазы (АсТ), щелочной фосфатазы (ЩФ) в печени, поджелудочной железе и сыворотке крови ремонтного молодняка кур, вакцинированных против ИЛТ