In the conditions of the Republic of Belarus there was realized a complex evaluation of producer bulls of different genotypes of origin for the further correction and breeding in different categories of agricultural enterprises. In course of the study there was conducted a preliminary (without quality evaluation of daughters) estimation of bulls which gave a precise performance of each bull, made it possible to correct its type and direction of breeding. Research made it possible to considerably increase the genetic trend in accordance with indexes of milk productivity which would make it possible to form a regional type of black-and-white cattle with the given indexes of productivity and reproduction. In course of the study there were analyzed the following breeds: black-and-white, Holstein, Hungarian breeding, Swedish breeding. Comparative evaluation of reproductive qualities of bulls in accordance with age-specific and breed types was presented. Body conformations of bulls of Holsten and Black-and-white of different ae-specific groups were stated. Results of complex evaluation of full-grown, under 5 year-old and replacement producing bulls of Holstein and Black-and-white breeds were presented.

In course of the realized investigation there was analyzed the dynamics of climatic resources of Belarusian Poozerye region (the Republic of Belarus) over the last 25 years. In course of he study there was analyzed the amount of effective yearly average temperatures of cultural landscapes of Belarusian Poozerye over 1998-2008. Also, there was presented the yearly average depth of precipitation in the analyzed area over 1984-2008. Results of 25-year studies over the climatic resources resulted the following: possibility of solution of a problem of plant productivity by means of concordance of physiological requirements of agricultural crops and the potential possibilities of cultural landscapes; notable increase of agroclimatic resources (increasing of amounts of active and effective yearly average temperatures; duration of vegetation period, etc.) requires the appropriate adaptation of cultivated agricultural crops; displacement of the northern border of the central agroclimatic region (isothermal curve 2000) to the north of the Belarusian Poozerye requires development of new approaches to management of this region; changes of growing conditions of agricultural crops requires specification of the existing technologies, scientific approaches to the specialization of the territory.

In the conditions of the Republic of Belarus there was studied the influence of a number of pigs in a group on swine productivity and blood indexes of pigs. In course of the study there were analyzed blood indexes of piglets before and at the end of the experiment. Research results showed that it was efficient to organize husbandry in small groups (10 heads per carriage). The adaptative period of animals in the conditions of husbandry in large groups (20 heads) was longer (the adaptation took place by the seventh day). In these conditions the average daily live weight gain of piglets was lower than in the conditions of small group husbandry on 5,1%. Research results showed that animal husbandry in the conditions of different number of heads per group did not render negative influence on morphological and biochemical blood composition.

In the conditions of the Republic of Belarus there was showed the possibility of import substitution of methionine and threonine preparations used for growing poultry birds by a new national developed in Belarus fodder additive L-homoserine. The chemical composition of the new feed additive L-homoserine is the following: amino acid L-homoserine; metabolizable energy; crude protein; crude fat; vitamins (B1; B2; B3; betaine; B5; B6; Bc); macro and trace elements (calcium; phosphorous; natrium; manganese; zinc; iron; copper). In course of the study there was analyzed the dynamics of body weight of broiler chickens; expenses of fodders per live weight gain; dynamics of body weight of replacement growing birds; indexes of second pen-feathers; dimensions of combs). Research results showed that addition of L-homoserine for broiler chickens diets was safe and nontoxic; the preparation showed the same growth promoting indexes as the foreign methionine and threonine preparations.

In the conditions of the Republic of Belarus there was determined the influence of experimental feed mixtures on the basis of humid preserved grain (conserved rolled grain of triticale; barley (Hordeum vulgare); oat (Avena sativa)) and protein, mineral and vitamin supplement (contains rape (Brassica napus) extraction cake; wheat bran; premix PKR-2; chalk; forage phosphate) on digestibility and metabolism of nutritive elements by young stock of cattle. There were presented recipes of the developed experimental feed mixtures and studied their influence on consumption and digestibility of nutritive elements of diets, metabolism of nitrogenous substances, calcium, phosphorous, as well as on hematological indexes. The proposed mixed fodders contained metabolizable energy; dry matter; crude protein; digestible protein; crude fat; fibre; starch; sugars; calcium; phosphorous; magnesium; potassium; sulphur; iron; copper; zinc; cobalt; manganese. In course of the study there was analyzed the consumption of the main nutritive elements; coefficients of their digestibility; nitrogen balance; balance of calcium and phosphorous; morphological and biochemical blood indexes.

In the conditions of the Republic of Belarus there was determined the influence of multi-enzymatic veterinary drug preparations Vitazim (contained a complex of enzymes of carbohydrases: xilanase; cellulose; beta-glucanase) and Ehkosim (universal multi-enzymatic complex: beta-glucanase; endo-xilase; and cellulase) on microbial composition of intestinal bacterial population. Research was realized by an example of layer hens of four-linear cross Highsex white at the age of 34-51 weeks. Regimens of administration of the analyzed preparations were presented. Research results showed promoted the development of the regenerative process of physiological media in intestines of poultry which was necessary for subsisting of normal flora of pathogenic bacteria. The studied preparations Vitazim and Ehkosim can be applied for the preventive treatment and therapy of intestinal dysbacteriosis, normalization of its microbial flora, as well as for the antibacterial therapy.

In the conditions of the Republic of Belarus there was studied the pathology and biology of cattle capillariasis. Capillariosis invasion rendered a substantial invasion on blood morphological composition which was revealed in lowering of erythrocytes and hematoglobulin, as well as in increasing of leukocytes quantity. There was noted the lowering of the natural resistance and immune reactivity. There were stated substantial deviations in protein metabolism which was expressed in lowering of total protein, quantity of albumins, changing of albumin and globulin coefficient, increasing of globulins. In the conditions of blood biochemical analysis of infesrated animals there was stated a disorder of vitamin and mineral metabolism; increasing of alanine aminotransferase and aspartate aminotransferase enzymes activity. Development of Capillaria bovis was realized in a direct line. In the natural habitat development of Capillaria bovis eggs varied from two up to three months.

In the conditions of the Republic of Belarus there was analyzed the efficiency of bactericidal action of tartaric acid aerosol for air sanitation of poultry buildings and increasing of broiler chickens viability. The bactericidal action was analyzed by the example of Staphylococcus aureus, Eschericia coli and Proteus vulgaris. In course of study there were analyzed biochemical indexes of blood and blood serum, lymphoid tubercle in proper mucous plate of trachea of broiler chickens after 6-time treatment with tartaric acid and Ekotsid C preparation. Research results showed that the analysed preparations did not render negative influence on metabolic indexes of broiler chickens and increase poultry viability. Application of tartaric acid did not cause pathomorphologic changes in tissues and organs of birds, stimulated the active proliferation of leucocytes in immune system organs (thymus gland; spleen; and lymphoid tissue).

In the conditions of the Republic of Belarus there was realized creation and evaluation of growth activity of serum and albuminous nutritional media. In the experiment there were used of 6 pathogenic strains: Leptospira pomona; Leptospira tarassovi; Leptospira grippothyphosa; Leptospira icterrohaemorragia; Leptospira conicola; Leptospira sejroe. For the Leptospira cultivation there were used the following media: serum-supplemented vitaminized medium on the basis of buck serum; serum-supplemented medium with a growth factor; serum-supplemented vitaminized medium with antlbody biosynthesis growth factor; semisynthetic Russel's medium in modification of V.I. Sitkov. Research results showed that the albuminous nutritional medium provided an intensive accumulation of Leptospira of all tested serogroups of Leptospira, but was suitable only for single bacterial inoculation. For the secondary hatching the albuminous media was unsuitable as it lowered the antigenic activity of Leptospira.

In the conditions of the Republic of Belarus by means of application of a scanning electron microscopy there was realized a morphological assessment of the efficiency of mono- and associated antiviral vaccines. It is shown, that analyzed biological preparations invoke in poultry a number of structural disorders among which it is possible to mention both immunomorphological changes, and pathomorphological processes. The highest reactogenicity was showed by of monovaccines against infectious bronchitis (produced by Research Institute of Animal Protection, Russia); infectious laryngotracheitis (Institute of Experimental Veterinary of S.N.Vyshelesskij, Belarus); and also an associated vaccine against infectious bronchitis, infectious bursal disease and Newcastle disease (Research Institute of Animal Protection, Russia). These vaccines caused essential structural disorders in tissues at a place of administration, liver and kidneys. Administration of the vaccine against infectious bursal disease and associated vaccines against infectious bronchitis, infectious bursal disease, infectious laryngotracheitis and Newcastle disease (Institute of Experimental Veterinary of S.N.Vyshelesskij) strengthened the processes of lymphatization in fabricic bursa. All studied biological products caused activization of morphological reorganization of immune apparatus of a spleen and did not render essential influence on thymus structure. | С использованием сканирующей электронной микроскопии проведена морфологическая оценка эффективности моно- и ассоциированных противовирусных вакцин. Показано, что указанные биопрепараты вызывают в организме птиц ряд структурных нарушений, среди которых можно выделить как иммуноморфологические изменения, так и патоморфологические процессы. Наибольшую реактогенность проявляли моновакцины против инфекционного бронхита кур (ФГУ ВНИИЗЖ, Россия), инфекционного ларинготрахеита (ИЭВ им. С.Н. Вышелесского), а также ассоциированная вакцина против ИБК, инфекционной бурсальной болезни и болезни Ньюкасла (ФГУ ВНИИЗЖ, Россия), которые вызывали существенные структурные нарушения в ткани на месте введения, печени и почках. Использование вакцины против ИББ и ассоциированной вакцины против ИБК, ИББ, ИЛТ и БН (ИЭВ им. С.Н. Вышелесского) усиливало процессы лимфатизации в фабрициевой бурсе. Все изучаемые биопрепараты вызывали активизацию морфологической перестройки иммунного аппарата селезенки и не оказывали существенного влияния на структуру тимуса.