In the article showed results of the researches of the influence on productive longevity of cows of such factors, as a linear belonging, a genotype of the father, type of selection are stated. The lead researches have shown, that more longer duration of use characterized the animals belonging to line Siling Trajdzhun Rockit 252803 - 4,5 lactations. Among daughters of various bulls the greatest term of productive use daughters of the bulls the Silach 158 - 5,0 lactations differed. At the maximal deviation in efficiency of ancestors (6001-7000 kg of milk) longevity of their daughters was the greatest and has made 4,18 lactations. The greatest influence on duration of economic use of cows was rendered by specific features of bulls (32,2%) and a linear accessory -12,0%. While the selection variant practically does not influence longevity of animals - a share of influence of 3,7%

Efficiency of level increase of colostrums' full value and natural resistance of calves at the expense of application additive stimulating immunity a preparation «Erakond» is proved in the article. Optimum doses and ways of application of a preparation are established

The influence of iron deficiency state on metabolic processes and intensity of lipids peroxidation processes at dawn-calving cows was analysed in the conditions of the Republic of Belarus. In course of study there was determined the intensity of lipids peroxidation processes in blood plasm depending on the level of hemoglobin and red blood corpuscle quantity. It was studied that in animals with low hemoglobin the oxidizing stress proceeded more actively than in animals with the normal hemoglobin level. Data analysis of lipids peroxidation processes showed that pregnancy condition was accompanied by strengthening of mentioned above processes. That fact was proved by the indicators of lipids peroxide oxidations presented both in absolute and in relative units. The content of diene conjugates, containing in 1 mg of lipids, was in 1,3-1,8 times higher at pregnant cows in comparison with non-pregnant ones, trieneketones content - in 1,2-1,6 times. Similar differences were observed in the process of analysis of diene conjugates and trieneketones values rated per 1 ml of plasma. More considerable differences were stated for trieneketones; the analysed indicator was in 1,6-2,1 times higher at pregnant cows

The nonspecific resistance of cows at the interlactation period was studied for the forecasting of the postnatal period progress in the conditions of the Republic of Belarus. Influence of the complex preparations Erimetrinis and Richometrinum on restoration of cow reproductive function was investigated. It was established, that the developed new complex preparation Erimetrinis possessed the uterotonic, antiphlogistic, pathogenetic and stimulating action. Evaluation of the presented preparation was tested have under production conditions and confirmed its high efficiency. After application of Erimetrinis there was noted a fast restoration of both endometrias histostructure, indices of cellular protection, and cow clinical characteristic. Microflora which was discharge from cow uterus content, which were sick with postnatal purulo-catarrhal endometritis, was sensitive and high-sensitivity Erimetrinis and had a zone of growth inhibition from 19,6 up to 36,1 mm, while after Richometrinum application it was sensitive except for staphylococcus and diplococcus in which the growth inhibition zone was from 15,1 up to 15,4 mm. Study of indicators of bactericidal activity of cow blood serum in course of treatment with the Erimetrinis it was established, that starting from the fourth day of the treatment the analysed indicator increased up to 56%, and by the moment of the clinical recovery it was 82,4+/-2,16%. Indicators of lysozymic activity of blood serum at the moment of cow recovery were 13,4+/-1,35 mmol/l. Essential changes were marked in the phagocytic activity of leukocytes, phagocytic numbers and phagocytic index. Cows which were subjected to treatment with Richometrinum all mentioned above indicators were increasing starting from the tenth day of treatment beginning, and clinical recovery was stated on 7,4 days later than after Erimetrinis application

In the conditions of biogeochemical zone of the Republic of Belarus the most important role in mineral metabolism is played by such major mineral elements as calcium, magnesium, phosphorus, potassium and trace elements - cobalt, cupper, iron, iodine, zinc, manganese, and selenium. Based on the above there was determined the interrelation between the content of these minerals in fodder and blood of milking and dry pregnant cows. As a result of realized study it was found out that the content of major mineral elements and trace elements in fodder did not always correspond to their level in blood. In the conditions of insufficient supply of Ca, F, Mg, K, Fe, Си and Co in cow diets, the level of potassium in blood was lower standard and the other analysed minerals were within the standard limits. There was stated the direct correlation relationship between the level of some biochemical indices and content of mineral substances in cow diets. Positive correlation was stated between the content of calcium and magnesium and cholesterin level in blood

In conditions of the Republic of Belarus much attention is given to optimization of energy and protein content in diets of dry cows. Analysis of the influence of different energy and protein ratio in dry cows diets on their productivity was realized. Increasing of protein and energy balance standards of dry cows during the winter period on 10 and 15% at the expense of introduction of protein, vitamin and mineral supplements (PVMS) made it possible to increase the daily average weight gain of animals on 5,4% and 12,2%, live weight of calves at a birth on 3,6% and 8,1% and their daily average weight gain over the first month - on 3,9% and 12,1%, respectively. Feeding with PVMS produced on the basis of peas and rape made it possible to raise the digestibility of nutritive substance on 1,4-14% and accessibility of all mineral substances on 0,4-10%. The increasing of energy and protein ratio on 15% in diets of pregnant dry cows rendered the positive effect on dairy efficiency. Fodder expenses for fodder unit production decreased on 5,5 and 6,8%, respectively. Inclusion of PVMS in mixture with pea and rape flour for dry pregnant cows during the summer period made it possible to raise their live weight on 5,9% and 9,7%, weight of calves at birth on 4,2% and 7,3%, and their daily average weight gain - on 5,7 and 9,4%. Optimization of power and protein fodder of pregnant dry cows promotes the increasing of milk yields in the first 100 days of the subsequent lactation on 5,1% and 9,9% and the decreasing of forage expenses for production unit on 4,6-9,1%

Analysis of supply of first-calf heifer diets with the mineral substances and their blood level at the first period of lactation as well as the development of the optimal feed formula of the mineral premix which could make it possible to neutralize the possible deficit of nutritive elements was realized in the conditions of the Republic of Belarus. It was stated that in animal diets against the background of protein and carbon misbalance there was noted the deficit of a number of trace elements such as manganese, copper, cobalt and zinc. In spite of sufficient content of calcium and phosphorus in cow diets, their concentration in blood plasma in first-calf heifers did not correspond to standard criteria, that was probably caused by vitamin D deficiency in cow rations. There was marked a low level of zinc, cobalt and manganese in whole blood of the majority of cows. With the purpose of correction of the first-calf heifer rations and for the prevention of possible hypomicroelementoses there was developed the composition of premix taking into account the necessary of cow feeding standards

There was studied the epizootic conditions on cattle rotavirus infections by the analysis of veterinary reporting of diagnostic organizations of Belarus and results of own research. Results of the data analysis about spreading of cattle rotavirus infection from 2002 for 2006 are presented. The material analysis has allowed to conclude, that annually in Belarus on rotavirus infections is registered on the average about 30 unsuccessful points. The obtained data testify that lethality for the reason of rotavirus infections makes calves from 15,9 to 32,9%. Decrease, in comparison with previous years, quantities fallen for the reason of rotavirus infections of calves testifies to purposefully spent specific preventive maintenance of the given infection, however lethality at rotavirus to an infection remains practically at one level. In the tabular form results of virology research of regional veterinary laboratory on cattle rotavirus infection on corresponding areas of Belarus are presented. From the data resulted in the table it is visible, that rotavirus allocation percent in various regions of the republic made from 9,8 to 56,7% at calves sick with enteritis. | Эпизоотическую обстановку по ротавирусной инфекции крупного рогатого скота устанавливали путем анализа ветотчетности диагностических учреждений Республики Беларусь и результатов собственных исследований. Представлены результаты анализа данных о распространении ротавирусной инфекции крупного рогатого скота за период с 2002 по 2006 годы. Анализ материала позволил заключить, что ежегодно в Республике Беларусь по ротавирусной инфекции регистрируется в среднем около 30 неблагополучных пунктов. Полученные данные свидетельствуют о том, что летальность телят по причине ротавирусной инфекции составляет от 15,9 до 32,9%. Снижение, в сравнении с предыдущими годами, количества павших по причине ротавирусной инфекции телят свидетельствует о целенаправленно проводимой специфической профилактике данной инфекции, однако летальность при ротавирусной инфекции остается практически на одном уровне. В табличной форме представлены результаты вирусологических исследований областных ветлабораторий на ротавирусную инфекцию крупного рогатого скота по соответствующим областям Республики Беларусь. Из приведенных в таблице данных видно, что процент выделения ротавируса в различных областях республики составлял от 9,8 до 56,7% у обследованных больных энтеритами телят.

Hepatospecific metabolic profile of blood serum in cattle with fat liver dystrophy has been studied. It has been stated that at this pathology the activity of aminotransferases, alkaline phosphatase hses; concentration of common cholesterol increases; lover indices of activity of cholinesterase, gamma-glutamiltranspeptidase and concentranion of serum albumin are observed. There was studied the hepatospecific metabolic profile of blood serum in cattle with fat liver dystrophy. The following biochemical indicators have been included: activity of some enzymes (alaninaminotransferase, aspartataminotransferase, gamma-glutamiltranspeptidase, alkaline phosphatase and cholinesterase), concentration of common protein, serum albumin, common cholesterol and common bilirubin, and also colloidal-sedimentary tests (thymol turbidity test and test on apolipoproteins-b). At fat liver dystrophy the activity of aminotransferases increases, specifying on the cytolytic processes proceeding in hepatocytes. Authentic increase of alkaline phosphatase enzyme and concentration of common cholesterol at animals testifies about developed intrahepatic cholestasia. Decrease of cholinesterase activity, concentration of serum albumin and the tendency to fall of enzyme gamma-glutamiltranspeptidase at fat liver dystrophy specify in infringement of albuminous exchange - a lack of proteosynthetic liver functions. Thus, offered for research hepatospecific metabolic profile of blood serum in cattle with fat liver dystrophy reflects proceeding pathological processes in body. In the tabular form data on activity of hepatic dependent enzymes at cows with fat liver dystrophy in comparison with healthy nonpregnant animals, indicators of colloidal-sedimentary tests, concentration of common protein, serum albumin in blood serum of cows with fat liver dystrophy and at healthy nonpregnant animals are presented.