A clinical field trial was performed to determine the effectiveness of an autogenous Salmonella Typhimurium bacterin compared with a commercial live S. Choleraesuis vaccine in pigs. The association between Salmonella shedding and weight gain was also investigated. Nine cohorts of weaned pigs, (330 to 350 pigs per cohort), were randomly assigned to 1 of 3 treatment groups (injection with S. Typhimurium bacterin, vaccination via water with S. Choleraesuis vaccine, or a control group receiving no vaccine). In each cohort, the average daily gain was calculated for a selected pen throughout the production stage. Pen (pooled) fecal samples were collected bi-weekly and cultured. The odds of Salmonella shedding in both vaccinated groups was higher than in the control group (P < 0.05). The prevalence of Salmonella shedding declined overall as pigs aged (P = 0.04). However, the control pigs showed the smallest decrease in Salmonella shedding over the entire production stage, while prevalence of Salmonella shedding in the vaccinated groups decreased twice as much as the control group over the entire production stage. Salmonella Typhimurium var. Copenhagen DT104, S. Cerro, and S. Agona, which had been isolated on the study farm previously, were recovered from pigs in this study. Shedding of S. Typhimurium var. Copenhagen decreased over time in both vaccine treatment groups. On the other hand, S. Cerro shedding rate was lower in the control pigs compared with vaccinated pigs and S. Agona could be recovered only from the samples collected from S. Choleraesuis vaccinated pigs. The pigs from pens with a higher Salmonella recovery rate experienced slower growth compared with pigs from pens where Salmonella was not isolated. This latter finding indicates that there might be an economic incentive for producers to try to control endemic salmonellosis if effective programs could be developed.

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 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 was analyzed the productivity of 13-18-month old young stock of cattle which was bred for meat with various levels of energy value nutrition. Also, there were noted their slaughter qualities and chemical composition of meat. Administration of diet rations with an increased level of exchange energy and the best indices of protein fissility rendered a positive influence on productivity of young stock of fattening cattle and made it possible to obtain 1103-1100 gram of body weight gain. As a result, the energy value gain was 22,9-22,6 MJ along with conversion of metabolizable energy at a gain - 24,7-25,3%. Consumption of metabolizable energy per 1 MJ along with body weight gain were within 4,7-5,0 MJ. Feeding of rations with various levels of the studied factor rendered the positive influence on slaughter qualities, made it possible obtain slaughter yield of 53,6-54,6% at an optimum ratio of nutrients in meat. Feeding of bull calves with diets with excessive content (up to 10%) of metabolizable energy made it possible to lower the prime cost of obtained breeding products on 0,55%.

In the conditions of the Republic of Belarus there was analyzed the efficiency of application of a whole milk substitute Biomilk-11 and feed additive SFDK-1 (biologically active enzymatic feed additive) for breeding of young stock of cattle, by an example of calves of black-and-white breed. In course of the study there was analyzed the composition of the feed additive SFDK-1 (weight fraction of dry matter; weight fraction of protein; content of amine nitrogen; cellulose fiber activity) as well as the physical and chemical indexes of the whole milk substitute Biomilk-11 (moistness; crude protein; crude fat; crude fibre). There were presented indexes of live weight gain of experimental and control calves as well as the dynamics of average daily weight gains in experimental group. Research results proved the efficiency of application of both additive for calves feeding.

In the conditions of the Republic of Belarus there were analyzed high productive traits of meaty calves and cross breeds bred in accordance with a system cow-calf, as well as the possibilities of using veal meat obtained in ecologically safe areas for infant food production. At the age of 6,5-7 months the weight of fresh carcass of bull-calves of sharolez breed in comparison with aberdin-angus х black-motley herdmates was on 41,6 kg (Р less than 0,001) higher, carcass yield and slaughter yield – on 13,8% (Р less than 0,001) and 13,6% (Р less than 0,001), respectively. The fat content in sharolez meat was 4,9% against 8,9%; protein - 21,9% against 18,8%. The black-motley suckling bull-calves surpassed their herdmates which were grown up by technology of dairy cattle breeding at the age of 6-6,5 months according to indexes of weight of fresh carcass - on 16,3 kg or 21,7% (Р less than 0,01); according to indexes in a slaughter yield - on 16,6% (Р less than 0,001); and according to indexes meat flesh in a carcass - on 1,5%. According to quality indexes, amino acid structure, acceptable concentration of toxic elements content, pesticides, antibiotics, radionuclides and other harmful substances the veal meat of calves which were bred on a system a cow-calve in ecologically pure zones proved to be important meat raw materials to produce infant food products.

In the conditions of Vitebsk region of the Republic of Belarus there was realized a programme on creation of breed type of Hereford cattle. In course of the study there were realized experiments on increasing the number of livestock of beef cattle breeding by means of accumulation cross breeding of black-and-white cattle with Hereford producer bulls as well as by means of pedigree breeding of Hereford cows and calves imported from Russia and Hungary for the production of marbled beef. Breeding background of obtained purebred calves was determined by DNA-testing method in accordance with the international standard of certification. Into the breeding group of created meat type of Hereford cattle in the analyzed cattle breeding enterprise there were selected 1183 heads, including 24,2% of purebred animals and 17,2% hybrids of the third and fourth generations. The breeding estimation thoroughbred Hereford cattle showed that all producer bulls belonged to the class elite-record. The percentage of cows and heifers of the elite-record class was 89,3% in the conditions of growing number of a thoroughbred livestock on 98 heads. Purebred young stock in number of 45 heads and their mother passed the estimation of their origin by DNA method-testing.

In the conditions of the Republic of Belarus there was analyzed the efficiency of application of an adsorbent mycotoxins Toxfin Dry (Belgium) for lowering of toxicity load on broiler chickens. In the course of the study there was given attention to poultry productivity, viability and forage expenses for broiler chickens breeding. There was developed a scheme of Toxfin Dry preparation feeding to broiler chickens. There were presented the results of weighing of control and experimental broiler chickens during the breeding periods; the basic zootechnical indices in the conditions of introduction Toxfin Dry; economic efficiency of its application. Research results showed that introduction of a mycotoxin adsorbent Toxfin Dry into diets of broiler chickens promoted the improvement of digestion and absorption of mixed fodder nutrients in a gastroenteric tract, that in its turn promoted the increasing daily average weight gain on 4,3%, broiler stock viability - on 2,6%; and to decrease the expenses for forages on 13,9%. On the basis of obtained experimental data it was recommended to include the mycotoxin adsorbent Toxfin Dry into rations of broiler chickens as a dry mix with mixed fodder in a dose of 5 g/kg of forage dry matter.

In the conditions of the Republic of Belarus there was analyzed the efficiency of feeding of a new protein vitamin and mineral additive containing national local protein and mineral raw material sources in diets of 12-16-month old heifers. Instead of sunflower extraction cake the heifers were fed with the protein-vitamin and mineral additive which contained rape grain (Brassica napus), lupine (Lupinus) grain as well as mineral and vitamin additives based on halites, phosphogypsum, phosphate, sapropel and premix in dose of 20-25% by weight as a part of mixed fodders. The additive was used against the background of rations with green mass from a cereal and leguminous mixture - 56-57%, mixed fodder - 36-37%, molasses - 6-7%. In accordance with nutritional value indexes the proposed additive rendered the positive influence on forage consumption, indexes of ruminal digestion, as well as on the morphological and biochemical blood composition. It application made it possible to obtain daily average weight gains of animals at the level of 812-827 grams within forage expenses of 7,0-7,2 сentner of fodder units. Inclusion of the protein vitamin and mineral additive with local protein and mineral raw materials in rations of calves made it possible to lower the mixed fodder cost price on 12-15% and the cost price of 1 centner of gain during the summer period - on 11-13%.