In the conditions of the Republic of Belarus there was studied the interrelation between content of major nutrient elements (calcium and phosphorous) and trace elements (iron, copper, cobalt, and manganese) in forages and blood of first-calf cows at the first and last stages of lactation. Also, there were developed formulas of mixed forages and a premix for these animals. The studies were realized at the Agricultural Production Co-operative Olgovskoe of Vitebsk region (Belarus). Research of analysis of forages and state of mineral metabolismat heifers made it possible to draw following conclusions: in cow rations there was marked the deficiency of vitamin D, as well as some trace elements (cobalt and manganese) in the conditions of calcium and phosphorus excess. In spite of a high content in a calcium in diets, it was noted than in blood plasma the concentration of this element was below the standard for the majority of animals. Lack of cobalt and manganese of whole blood of cows was connected with a low level of these elements in cow diets. The surplus contents of copper in forages and blood of animals against the background low activity of ceruloplasmin the weakened antioxidant defense of heifer cows. For preventive treatment of possible hypo trace element deficiencies and metabolic disorders of heifer cows at the final stage of lactation there can be recommended the correcting of cow diets with inclusion into their composition of the developed for compound of mixed fodder and premix.

In the conditions of the Republic of Belarus there was studied the influence of various doses of dolomite on productivity, egg quality and a mineral metabolism of laying hens. The research was realized by an example of laying hens of Highsex Brown. The experimental hens at the age of 250 days old were divided into 4 groups on 60 heads in each by means of analog method. Laying hens of the first (control) group were fed with a basic diet including 5% of a soya cake (cockle-shell), and hens of the second, third and fourth (experimental) groups instead of a soya cake were fed with a mixed fodder with addition of a mineral additive of dolomite. Hens of the second group were fed with the additive at a rate of 2%, the third group - 3%, and the fourth group - at a rate of 5% of weight of dry matter of forage. During the experiments there were maintained optimum parameters of microclimate, recommended temperature and light regimes and a sufficient ultra-violet irradiation. As a result of the realized research it was established, that use of the mineral dolomite additive in feeding of laying hens proved to be possible as a substitute of an expensive import cockleshell. Use of various doses of dolomite promoted improvement of mineral metabolism, increasing of productivity and improvement of egg quality of laying hens.

In the conditions of the Republic of Belarus there was realized a comparative study of meat productivity of mongrel Gereford х black-and-white heifers ad purebred black-and-white heifers in the conditions of different levels of concentrated feedstuff in cattle diets; and determine the most efficient and long-term method of animal breeding for meat. Research results showed that breeding of meaty of hybrids of Gereford х black-and-white heifers of the second generation without using the feeding concentrates in their diets or on using rations with a low rate of feeding concentrates (10-20%) proved to be more effective, than breeding of purebred black-and-white herdmates (for which specific density of the concentrated forages in diets made up 20% through pregnancy). Hybrids on Gereford breed in accordance with meat productivity level surpassed the purebred black-and-white animals. The most considerable results were marked at hybrid heifers with relative density of concentrates in a ration of 20% which in accordance with slaughter weight indexes surpassed the herdmates of black-and-white breed on 39,1 kg or on 23,68%, in accordance with slaughter yield - on 8,2%, in accordance with fresh carcass weight - on 37,9 kg or on 23,8%, in accordance with weight of inner porc - on 1,19 kg or on 20,62%.

In the conditions of the Republic of Belarus there were analyzed productivity indexes of sows of different families and family groups and their compatibility with male pigs of different lines of Belarusian meaty breed and Landras. On the basis of the realized research it was marked, that according to the number of piglets in a litter and multiple pregnancy distinctions between breeding sows of Landras breed and Belarusian meaty there was not observed. From sows of both breeds in average per farrowing there was obtain 11,0 - 11,2 piglets, including 10,4 - 10,5 live piglets, that exceeded requirements of the first class of the instruction on evaluation of pigs on 4,0 - 5,0%. At the same time, sows of the Belarusian meaty breed had litter weight at weaning in 40 days of 104 kg, that was authentically higher on 8 kg or on 8,3% (Р less than 0,001), than sows of Landras breed. In each breed there were some distinctions in sow productivity by families and in breeding with boars of different lines.

In the conditions of the Republic of Belarus clinic and production conditions there was analyzed the prophylactic and therapeutic efficacy of a new national complex iron dextrane preparation Ferovital against deficiency (nutritional) anemia of new-born cattle and swine. In course of the study there were analyzed results of hematological and biochemical tests of blood of piglets which were administrated with Ferovital preparation. There were also marked the general economic index: live weight gain, disease incidence, piglet death rate, etc. Research results showed that the Ferovital preparation had an expressed prophylactic and therapeutic efficacy both in clinic and production conditions.

In the conditions of the Republic of Belarus there was realized a comparative study of peculiar features of influence of combined application of Khelavit preparation and protein-vitamin-mineral feed supplements Khendriks and Spaeta-kontsentrat on health status of cows and quality of obtained cow milk after application of these preparation for the preventive treatment of osteodystrophy. In course of study there were analyzed haematologic and biochemical blood indexes of cows after application of the experimental preparations. Results of physical and chemical indexes of milk were presented. Research results showed that the analyzed protein, vitamin and mineral feed supplements caused the normalization of biochemical blood indexes in comparison with animal of a control group. Besides, application of mentioned above drugs promoted the increasing of veterinary and sanitary quality and technological properties of produced milk.

In the conditions of the Republic of Belarus there was studied the influence of high degree of cow productivity on the course of down-lying and state of endocrine status of animals and their reproductive qualities. Application of veterinary preparations Katozal and Ovoton made it possible to control the functional activity of cow dam and ovary providing the increasing of cow reproduction qualities. Results of tests of estradiol-17 beta and progesterone in blood serum of experimental and control groups cows were presented. Application of Katozal and Ovoton veterinary drugs made it possible to cause heat and insemination of 86,5-91,3% of cows. At the same time, according to the results of the first insemination the highest results were obtained at cows with low productivity indexes – 60,9% and according to productivity increasing this index lowered up to 32,7% and 29,8%, respectively. According to the results of all insemination in cases of 3500-5000 kg productivity only 2 cows (8,7%) were nonbearing.

In the conditions of the Republic of Belarus there was analyzed the influence of inclusion into broiler chickens diets of probiotoc preparation Bifidoflorin zhidkij (liquid) and prediotic veterinary drug Biofon AIL on the natural resistance, hematopoiesis, growth, metabolic function, development and viability of broiler chickens. In course of the study there was analyzed the dynamics of total haemoglobin, total protein of blood serum, albumins and globulins of broiler chickens which were fed with veterinary drugs probiotoc Bifidoflorin zhidkij and prediotic Biofon AIL. Indexes of chicken viability and life weight gain were marked. Research results showed that application of the presented veterinary preparations rendered the growth promoting action, lowering of disease incidence, increasing of chicken viability, increasing of live weight gain and stimulation of metabolic processes in the most intense period of poultry growing. All these factors were expressed in highest degree after the combined application of the probiotic and prebiotic veterinary drugs.

In the conditions of the Republic of Belarus there was studied the possibility of application of biotechnological methods of correction of sexual function of infertile cows and heifers (oestrus stimulation and synchronization) a dairy cattle breeding farms with high breeding productivity indexes and simultaneous metabolic function diseases. In course of the study there were applied clinical, cytodetection technique, haemotological, biochemical and analytical methods. Results of three-year studies of pathological metabolic disorders of cows (chronic acidosis; chronic ketoacidosis; dystrophic liver affection; renal irritation syndrome; disturbance of calcium and phosphorous ratio; trace element deficiencies; hypovitaminoses) were analyzed. Structure of obstetric-gynecologic pathology in experimental dairy cows herd was presented. Research results showed that high reproduction indexes of cows were the contributory cause for development of metabolic disorders. In such conditions for the efficient stock reproduction it was proposed to apply the mandatory hormonal stimulation of sexual function by means of application of the Ovsinkh scheme.

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.