In the conditions of the Republic of Belarus there was determined the therapeutic efficacy of combined application of a complex antibacterial veterinary drug (containing lincomycin and spectinomycin) and Trivitim for the treatment of calves with respiratory diseases. In course of the study of 12 1-1,5 month old calves with respiratory diseases there were analyzed the hematological blood indexes, white blood cell differential and content of total protein in blood serum before the beginning of treatment and on the seventh and fourteenth days after beginning treatment. Research results showed that application the antibacterial veterinary drug in complex therapy with Trivitim in treatment of calves proved to be efficient. Their administration shortened the terms of recovery and prevented animal death as well as promoted the normalization of hematological and biochemical blood indexes.

In the conditions of the Republic of Belarus there was studied the influence of methods and means of spot heating and localization of warmth on indexes of microclimate in piglet breeding houses and resting area of piglets and their growth parameters. In course of the study there taken into consideration the indexes of an average temperature on piglet resting area housings; atmosphere relative humidity, air velocity, content of carbon dioxide, content of hydrogen nitride in the housing and resting areas of piglets. Research results of microclimate of swine breeding areas and resting areas of piglets under different means and methods of heating and warmth localization showed that the it was the most efficient to add for the local heating in the first three weeks of suckling period the glow-discharge tubes or in suckling period or weanling periods - the heated floors; and in suckling period - brooders in the form of tops with shields.

In the conditions of the Republic of Belarus there was studied the morphology and growth dynamics of vomeronasal cartilage of swine at postnatal period. The vomeronasal cartilage covers the vomeronasal body outside. Lateral and medial bases of vomeronasal cartilage formed an antrum in which there was an organon vomeronasal. The most intensive growth of a cartilage of pigs occurred in the first two months of animal life. Arrangement of cartilage was dissymmetric - at the right it was sited more caudad than at the left; this fact caused the differences in its dimensions at the transverse sections.

In the conditions of the Republic of Belarus there was analyzed the efficiency of application of organic form of selenium Sel-plex in feeding of producer bulls. In course of the study there was showed the dynamics of live weight and average daily weight gain of producer bulls; blood indexes of analimals by the end of the experiment; sperm quality of experimental bulls. As a result of research it was established, that application of organic form of selenium Sel-plex in feeding of breeding bulls during the summer and winter periods in a dose of 0,4 mg/kg of dry matter of a ration promoted the increasing of daily average live weight gain on 6,4-8,1%, improvement of morphological and biochemical blood structure, increasing of indices of natural resistance on 0,5-6,1% and sperm production quality - on 7,3-28,0%.

In the conditions of the Republic of Belarus there was analyzed the influence of the following paratypical factors on cow productive longevity: age of the first calving; milk yield at the first lactation; and a birth season. At the experimental animals there studied the indices of dairy efficiency: a lifelong milk yield (kg); a lifelong yield of dairy fat (kg); the total duration of the lactation period (days); duration of practical use (lactations). There was noted a tendency of increasing of a term of productive use and lifelong productive efficiency at the animals the practical economic use of which was begun in later terms. The insemination of these animals was approximately realized at the age older than 21 months. Also it was stated that in accordance with all investigated indices (except for a milk yield per one day of lactation) the highest indexes were typical for cows which had the least milk yield at the first lactation.

In the conditions of the Republic of Belarus it was determined that application of monocalcium phosphate in a dose of 10 gram per 1 kilogram of mixed fodder and specified doses of trace elements (cuprum; zink; cobalt; manganese; iodine) in diets of growing pedigree bull calves made it possible to increase indices of body weight of young cattle stock of the third experimental group in comparison with animals of the first and the second groups on 18,3 and 11 kg or respectively on 3,9 and 2,3%; as well as to increase the intensity of their growth. The highest daily average live weight gain was noted at animals of the third experimental group – 1062 grams. It was higher than at bull calves of the first and the second groups respectively on 31,3 and 12,8 grams, or on 3 and 1,2%. Application of monocalcium phosphate in a dose of 10 gram per 1 kilogram of mixed fodder favorably affected the formation of desirable type of sexual behavior and indices of semen production quality. Thus, in the third experimental group in comparison with animals of the first and the second groups the volume of ejaculate was on 0,2 and 0,1 ml higher (or on 5,8 and 2,9%); quantity of sperm in ejaculate - on 0,7 and 0,3 billion, or on 35 and 15%.

In the conditions of the Republic of Belarus there was realized a scientific and economic experiment on studying the influence of a multi-enzyme feed additive on productivity, viability, growth and development of calves. The multi-enzyme additive contained in its formula xilanaza; glucanase; cellulose; and dolomite (as a filling agent). It was determined that young growth of cattle which were fed with the multi-enzyme additive in dose 1 gram per 6 kilogram of milk by the end of the experiment had a live weight gain on 13,6% higher than in a control group. Calves which were fed with the additive were characterized by more stretched constitution, had well developed thorax and good development of skeleton in comparison with analogues from the control group.

In the conditions of the Republic of Belarus there was analyzed the efficiency of administration of nonconventional feed materials in diets of highly productive cows and its influence of indexes of natural resistance at different physiological stages of animals. In the process of studying of adaptation processes of highly productive cows at different stages of lactation it was determined that feeding with nonconventional melanoidin-humic additives at different physiological periods rendered a positive influence of highly productive cows, promoted the increasing of natural resistance of animals and improvement of immuno-humoral blood indexes. Administration of an additive Ehkolin in a ration of highly productive cows with stimulation for increasing milk flow in a dose of 100 ml per head promoted the increasing of blood serum bactericidal activity on 5,2%, beta-lysine activity - on 7,2%. Feeding of animals at a basic lactation period with 50 ml of preparation Ehkolin-2 provided the maximum increasing of lysozyme activity of blood serum (on 6,2%) and beta-lysine activity of blood serum (on 12,7%), and also promoted the activation of leukocytopoiesis. Addition of Ehkolin-3 in ration structure of dry cows in a dose of 750 ml increased the indexes of lysozyme activity of blood serum on 7-8,6%, bactericidal activity of blood serum - on 2,2-3,6% and beta-lysine activity of blood serum - on 2,2-3,6%.

In the conditions of the Republic of Belarus there was studied the efficiency of application of granulated and extruded lupine (Lupinus) in feeding of bull claves. It was determined that after lupine extruding the quantity of sugar in it increased on 45% due to lowering of starch content. The inclusion of extruded lupine into bull calves diets made it possible to increase the digestibility of dry and organic substances, protein and nitrogen-free extractive substances. The highest average daily weight gain (842 gram) was stated at claves which were fed with mixed fodder with 15% of extruded lupine; this was on 7,5% than in a control group. In the conditions of feeding with the granulated lupine the average daily weight gain increased on 5,3% in comparison with crushed one. In course of study there was analyzed the dependence chemical composition of lupine on the processing method; blood composition of the studied animals; diets of experimental animals; digestibility of nutrient substances of forages; balance and intake of nitrogen; biochemical blood composition; changes of live weight and average daily weight gain.

In the conditions of the Republic of Belarus there were determined the doses of application of siliceous sapropel as well as there were studied the indexes of ruminal digestion and digestibility of diet nutrient substances by bull calves. The studied siliceous sapropel of the lake Pribylovichi (Belarus) occurence on 42% consisted of organic substances and on 58% - of mineral substances: calcium, phosphorus, magnesium, potassium, sodium, iron, zinc, manganese, and copper. The studied sample of sapropel did not render toxic action on test objects of infusorian Tetrahymena pyriformis in the conditions of its addition into the basic forage in number of 1%; 3%; 5%; and 10%. However, its higher concentrations (10%) retarded the development of Protozoa. Feed additives with the content of siliceous sapropel in mixed fodder in dose of 1%, 3% and 5% increased the relative biological value of forage in the experiments on test objects of infusorians Tetrahymena pyriformis in the average respectively on 5,4%, 5,0 and 2,6%. Higher concentrations of sapropel in mixed fodder (5 and 10%) lowered its nutritional value. Inclusion of siliceous sapropel in bull calve rations activated the enzymatic processes in farding bag and increased the digestibility nutritive elements on 2,3-3,6% except for protein, digestibility which was practically at identical level at animals of all groups.