Results of serological examinations of blood serum of sheep on revelation of virus respiratory infections (parainfluenza-3, adenovirus and respiratory syncytial) realized in the conditions of the Kyrgyz Republic were presented. Research results showed that in farm and peasant farm holdings of all studied districts of the Kyrgyz Republic of three types of pneumo viral infections simultaneously give high levels of antibody titers in relation to parainfluenza-3 – 1:128, adenovirus – 1:32, respiratory syncytial infection – 1:16. In some districts sheep population was diseased only by parainfluenzal infection in relation with titer of specific antibodies 1:256

The methods and results of determination of safety and relative biological value of carps (Cyprinus carpio) with philometroidosis and breams (Abramis brama) with ligulosis depending on infestation intensity with application of test-object Tetrahymena pyriformis realized in the conditions of the Republic of Belarus were presented. Research results showed that lowering of reproduction degree of protozoan on 20-30% could testify to the presence of light toxicity. Suppression of infusoria reproduction up to 30% with the simultaneous lowering of actions activity, disturbance of its character and availability up to 10% of inflected cells could testify on the moderate degree of toxicity. Lowering of infusoria reproduction degree on 30-50% with the simultaneous presence of 10-20% of cells with the affected character of motion, form and dead testified to evident toxicity of products. Lowering of infusoria toxicity on 50% and higher, presence of cysts, distorted cells, and ghosts testified to high product toxicity. Research results established that in case of high invasion intensity meat of carp philometroidosis had low toxicity (2 points). Meat of breams with ligulosis and moderate invasion intensity had low toxicity level (2 points), and in case high invasion intensity – moderate (3 points). The relative biological value in case of philometroidosis was on 13,29-28,41% lower in comparison with meat of healthy carps, and in case of ligulosis - on 18,66-57,29% in comparison with healthy breams meat

Results of studies of peculiar properties of progesterone content in blood serum of outbred female rats under the influence of intensive ionizing radiation against the background of stress stimulation realized in the conditions of the Republic of Belarus were presented. There were the following animal groups: 1. controlled rats; 2. irradiated rats; 3. stressed animals; 4. rats subjected to ionizing radiation and stress. Research results showed that concentration of progesterone in serum blood of female rats in 3 days after immobilized stress decreased on 40% in comparison with the control indexes. More intensive decreasing of hormone level took place after irradiation in dose of 1 Gy (on 62% in comparison with the controlled group). Combine activity of ionizing radiation and stress involved the decreasing of hormone concentration on 25% in comparison with the controlled group. In ten days there was the restoration of changes. Increase of progesterone concentration in blood serum took place in all tested groups. Hormone level in blood serum of irradiated rats increased on 46,04 nmol/l in comparison with results of the third day after irradiation. Hormone level in blood serum of stressed animals increased on 11,63 nmol/l, in group subjected to the combined activity of ionizing radiation and stress – on7,65nmol/l. On the thirtieth day the indexes of progesterone concentration in blood serum of irradiated rats, stressed rats and rats subjected to ionizing radiation and stress were almost similar to the control indexes

Methods of increasing the efficiency of semen fertilizing capacity in vitro with application of hormonal and biophysical methods of influence, as well as the determination of metabolic criterion of spermium viability were studied in the conditions of the republic of Belarus. Research object was frozen-deiced sperm of cattle. Research results showed that entering of 50 mkg/ml of prostaglandin into capacitation media increased the breaking level on 2,3-3,1%, but at the same time there was the decreasing of embryo output at the pre-implantation stages. Increasing of estrophan concentration in media for capacitation up to 100 mkg/ml, and its addition into media for fertilization made it possible to increase the embryo output at the stage of morula-blastocyte up to 1,6-18,5%. Application of 8mg/ml of caffeine as a capacitation agent for the preparation of cattle sperm for fertilization in vitro made it possible to obtain embryo output of 16,7% with breaking level of 25,9%. Influence of directed polarized light on semen after its maturation was more efficient in comparison with the influence on it just after swim-up procedure; the output of pre-implantation embryos was 16,7% against 12,9%. Application of laser radiation made it possible to get 14,7 % of morula-blastocytes. Intensity of sperm breath (0,41-0,63 tg), intensity of lipid peroxidation (0,88-0,97 conditional units /10E6 cells), intracellular content of adenosine triphosphate (0,97-1,60 Nm/10E6 cells) and membrane potential (33-35 uV) in the conditions of matured in vitro oocyte made it possible to get 16,4-17,3% of pre-implantation embryos with the breaking level of 39,8-42,3%

Evaluation of a quantity and phagocyte activity of leucocytes, immunoglobulins, T- and B-lymphocytes in blood serum of sheep in the process of stimulation of central nervous system with caffeine sodiobenzoate for the increasing of nonspecific animal resistance was realized in the conditions of the Republic of Belarus. Romanov yeld ewes were divided into two groups. Experimental sheep were entered caffeine sodiobenzoate intramuscularly in dose 0,012 g/kg of live weight twice a day with 6 hours interval. Controlled group of sheep were entered physiological salt solution in accordance with the same scheme. Blood samples were taken before preparation entering and after 1, 3, 6, 12 and 24 hours of test beginning. Immunoglobulin concentration in blood serum was estimated by electrophoresis method in polyacrylamide gel. Quantity of T- and B- lymphocytes was estimated by active rosette test. Phagocyte activity of leucocytes was estimated with application of germ culture St. albus. Leucocytes number was accounted in Gorjaev's chamber. Research results showed that under conditions of central nervous system stimulation by caffeine sodiobenzoate there was stated the increasing of nonspecific resistance. It was proved by the increasing of the total number and phagocytic activity of leukocytes, immunoglobulins (IgG, IgA and IgM), T- and B- lymphocytes

The problem of creation of improved conditions for cattle oocyte maturation in vitro was studied in the Republic of Belarus. The objects of study were cattle oocytes and embryos of early preimplantation stages of development obtained in vitro conditions. Research results showed that application of bovine serum in complex with embryonic or fetal serum in the process of oocyte cultivation in vitro conditions made it possible to obtain 35,5-44,8% of breaking down cells and 16,1-17,2 % of embryos at the stage of morula-blastocyte. Entering of 0,02 ng/ml of gonadotropin-releasing hormone (Surfagon) into media for oocyte maturation at the cost of regulation of the processes of growing and development of oocyte-cumulus complexes made it possible to increase of yield of matured till the stage of metaphase II oocytes up to 89,3 %. At the same time, the yield of divided embryos after fertilization increased on 2,5 % in comparison with control indexes and amounted 45,2 %. Research results showed that the synthetic phytohormone epibrassinolide could be used as a biologically active factor in the process of getting early embryos in vitro in concentration of 2 x 10E-7 – 2 x 10E-9 mole/l. It made it possible to get 46,4-55,0 % of divided cells and 14,2-16,2% preimplantation embryos

Efficiency of cultivation of cow preimplantation embryos and support of pluripotent properties in different nutritive media was analyzed; a method of getting early embryos in vitro for the genetically engineered purposes was developed in the conditions of the Republic of Belarus. Oocyte separation was realized in 3; 3-6; 6-9; and 9-12 hours after ovariectomy for the studying of the influence of storage period of ovaries on the output qualitative embryos. Oocyte separation was realized by bisection with adding of 1% of fetal cattle serum, 10 units/ml of gentamicin and 1 unit/ml of heparin. Oocyte-cumulus complexes maturing took place in CO2-bath with 5% of CO2 in atmosphere of maximum humidity and temperature of 38 deg C in TS-199 (Sigma) media with entering of 25 mM/l of buffer Hepes, 10 unit/ml of gentamicin and biologically active substance (20 % of fetal calf serum, 10 mg/ml of bovine serum albumin and 5 % of estrous cow serum with 10 mg/ml of bovine serum albumin). Research result showed that application of 10 mg/ml of bovine serum albumin into TS-199 media made it possible to increase the yield of cattle embryos at the preimplantation stages in vitro conditions on 19,1%, as well as to increase the fetal calf serum in quantity 15% to the nutritive media volume up to 16,0 %. Application of sodium pyruvate and calcium lactate in the process of cultivation of early cattle embryos obtained in vitro conditions made it possible to increase the yield of preimplantation embryos on 5,4 %. Specifically, the level of transformation of morulas into blastocysts was 44,4 %