In the conditions of the Republic of Belarus there were analyzed the efficiency of 13-18-month old young stock of cattle bred for meat in the conditions of various energy value nutrition levels with the determination of nutrients intake of a diet. It was established that use of rations with various level of metabolic energy and protein breakage rendered the positive influence on nutrient digestibility of rations. This made it possible to improve the digestibility of dry and organic substances, nitrogen-free extractive substances and fibre at the bull calves which were fed with 63% of cleavable protein, as well as to increase the metabolic energy up to 10% in the ration, surpassing the control indexes respectively on 3.1; 2.5; 2.8; and 2.9 items. Adjournment from the acquired nitrogen considerably increased and made up to 64-70%. Productivity of fattening young cattle stock made it possible to obtain 977.7-1011.0 gram of live weight gain. As a result, the growth energy was stated at the level of 15,90-17,33 МJ in the conditions of conversion of metabolic energy into growth of 13,81-14,26% and expenses of metabolic energy of the ration per 1 MJ in live weight gain of 4,72-5,46 MJ.

The research in RUP Scientific and Practical Center of Animal Breeding of National Academy of Sciences on such parameters as consumption of forages, processes of rumen digestion, morphological and biochemical structure of blood has shown that usage of wet grain preserved with Kormoplus for young cattle fattening has a positive effect on physiological condition and digestibility of nutrients and promotes nitrogen usage by animals that increases at 7,0 and 1,6%

Influence of 33 imported heads Landrace breed boars of foreign selection on feeding performance and meat productivity of swine of the Belarusian Meaty breed was studied in the conditions of the Republic of Belarus for the enhancement of Belarusian breeds genealogical structure. There was stated the positive influence of Landrace Breed on feeding performance and meat productivity of mixed bred stores obtained after the introductive crossing with sows of Belarusian Meaty breed which was expressed in the predominancy of mixed bred hogs over the purebred ones at the stage of fattening performance test: at the age of reaching 100 kg body weight – on 0,7%; at average daily weight gain - on 1,5%; at feed consumption - on 1,2%. Mixed bred stores also had thinner back fat (on 0,9 mm) and bigger loin (on 0,4 square cm). There was stated the one-sided influence of boars of Landrace Breed on feeding performance and meat productivity indices of mixed breeds. It was established, that hybrids of four lines (Zaboj, Zalet, Zont and Bison) with regard to control groups showed the effect of heterosis at age of achievement of body weight of 100 kg, at a daily average weight gain and at forage consumption in the following rates: 1,5% (Р less than 0,05), 2,8% and 1,5% (Р less than 0,05) for Zaboj line; 2,3%, 4,9% and 2,1% (Р less than 0,01) for Zalet lines; 1,4%, 3% and 1,5% (Р less than 0,05) for Zont lines; 3% (Р less than 0,001), 6,7% and 2,7% for a line of Bison. In meat productivity indices there was stated the in-between character of inheritance which caused the decreasing of fat thickness and increasing of loin eye area at descendants of trial groups of lines: Zaboj, Zalet, Zenit, Zont on 0,88 mm (Р less than 0,05) and 0,6 square cm, 1,7 mm (Р less than 0,01) and 2,1 square cm (Р less than 0,001), 1,3 mm (Р less than 0,01) and 0,9 square cm, 1,4 mm

In the conditions of application of enzyme preparations there is the possibility of inclusion into mixed fodders structure of such cheap fodder grains as rye. Determination of the optimal dose of introduction of the liquid enzymatic fodder additive (xylanase – 8800 units; phytase – 600 units; cellulose – 880 units; r-gluco – 4000 units; a- amylase – 200 units) and its influence on stores productivity during the completion of growing and fattening periods was realized in the conditions of the Republic of Belarus. Research results showed the following: inclusion into mixed fodders of the increased amount of rye grain (without the enzyme additive) for stores feeding during the completion of growing (20%) and fattening (30%) periods did not render negative influence on experimental animals; the optimal dose of the trial enzyme for stores during the completion of growing period - (SK-21 including rye grain - 20%) was 200 ml per 1 t of mixed fodders; the optimal dose of the trial enzyme for stores during the fattening period (KDS-26 including rye -30%) was 150 ml per 1 t of mixed fodders. Application of the experimental fodder additive promoted the increasing live weight gain. There was noted the tendency of the positive influence of the analyzed enzyme on dry and organic matter, fat, dietary fibre and nitrogen-free extractive substances digestibility

The purpose of the research was establishment of hepatic diseases spread in cattle fattening. Trials were conducted with total number of hybrids IV-V generation of black-motley heifer with pedigree Hereford bulls. It has been established the wide spread (22,4%) of hepatic pathology. The leading place among all hepatic pathologies belongs to fatty hepatosis (13,4%) with weakly expressed symptoms, decrease of serum protein level, albumin, glucose and increase of bilirubin, globulins, hepatic enzymes and strong pathology-anatomical and histological manifestations. In the tabular form results of histologic research of liver, some biochemical indicators of blood of healthy and sick animals (M +/- m), the clinical symptoms revealed during the various periods are resulted | Целью исследований являлось изучение структуры и установление широты распространения болезней печени у крупного рогатого скота на откорме. Опыты проведены на широком поголовье помесей IV-V поколения тёлок чёрно-пёстрой породы с племенными быками герефордской породы. Установлено широкое (22,4%) распространение гепатопатий. Ведущее место среди различных форм поражения печени принадлежит жировому гепатозу - 13,4%, морфофункцинальный профиль которого определяется слабо выраженными клиническими симптомами, уменьшением уровня общего белка, альбуминов, глюкозы, повышением концентрации билирубина, активности гепатоспецифических ферментов, а также всех фракций глобулинов, яркой и характерной патологоанатомической и гистологической картиной. В табличной форме приведены результаты гистологического исследования печени, некоторые биохимические показатели крови здоровых и больных животных (M +/- m), клинические симптомы, выявленные в различные периоды

In the conditions of the Republic of Belarus there were determined the fattening and slaughter qualities of swine as well as the evaluation of their pork production in the conditions of inclusion into their diets of a biologically active substance on the basis of field caraway (Carum carvi L.). Research results showed that in the production conditions the administration of the biologically active additive in a dose of 7 gram per 100 kilogram of live weight of pigs made it possible to increase their daily average gain from 627,9 grams in a control group up to 687,2 grams (or on 9,44% (P less than 0,999)), to increase their preslaughter and slaughter weight respectively on 3,76% and 6,42%, dressing percentage and carcass yield – respectively on 1,71 and 1,67%. According to the indexes of meat quantity in diverting weirs of the experimental pigs surpassed the control group on 3,03%, or 2,70 kg. The fat content in the half carcasses of the experimental group was authentically lower than the indices of control animals on 0,48 kg or on 2,18%. The hock weight of experimental animals with high confidence exceeded pigs of the control group on 1,15 kg, or on 10,45%. They practically did not differ from the control group according the indexes of thickness of pork fat at the level of 6-7 chest vertebras, and in the area of a muscular eye surpassed them on 4,0 square сm or on 7,72%.

In the process of monogastric animal feeding, including pigs, the special role is played by the quality of coarse grain crops as they compose 70-75% of swine ration structure. Determination of fodder productive effect on fattening swine was realized in the conditions of the Republic of Belarus. The basis of the analyzed fodder was formed by fodder grain of extra fine grade. Research results showed the following: inclusion of extra fine grade barley (Hordeum vulgare) and wheat (Triticum aestivum) (chosen in accordance with the standard of the Republic of Belarus) into all-in-one mixed fodders SK-26 and SK-31 for fattening swine made it possible to obtain higher productive capacity of the experimental animals in comparison with the identical mixed fodders containing barley and wheat of other grades (chosen in accordance with All-Union State Standard 28672-90); in the experimental groups the average daily weight gain in course of the fattening period was on 34 grams higher, and the average selling weight of 1 head - on 4,1 kg than in the control group. Swine which were fed with the presented mixed fodders with grain extra fine grade showed fewer deviations from the rated value of metabolism (blood serum protein and its fractions, calcium, phosphorus, acid capacity) in comparison with the control groups

Belarus is included into number of the leading countries of the world which provide the increasing of the expansion rates of milk production and dairy products on a per capita basis. However, the agricultural enterprises of the Republic of Belarus annually spend approximately 800 thousand tons of whole milk that makes about 20% from the general milk yield for manufacturing expenditures in the process of livestock operation. The purpose of research was working out of a new premix structure and zootechnic requirements to its use in structure of milk replacer, produced on hydrodynamic installation. The optimum doses of amino acids, vitamins and mineral substances promoted the increasing of calves daily average weight gain during the dairy period on 5,4% (788,5 g instead of 748,1 g), reducing of expenses for forages per 1 kg of weight gain - on 6,5% (2,9 fodder units against 3,1 fodder units) and the decreasing of the prime cost production for fodder expenses - on 4,7%. There was presented the composition and nutritive value of the analysed whole milk replacer. Usage of local sources of protein-fatty raw materials of plant origin, and also secondary resources of processing of whole milk in the content of milk replacer for young cattle allows to completely refuse from expensive components delivered from abroad and to lower their cost

Research was directed towards selection of national, accessible and cheap ingredients of whole milk replacers in the conditions of the Republic of Belarus. The efficiency of compounding preparation and its use in calves feeding at an early age was analysed. There was developed the technological scheme of application of hydrodynamic installation which operates according cavitating principle and makes it possible to receive the homogeneous and finely divided mass directly from grain forage that is very important for preparation of milk replacer. New equipment gives the chance to lower power consumption on 17%, to receive economic benefit. During testing of developed of milk replacer-1 (used for calves feeding since one month old) and milk replacer-2 (used for calves feeding since two months old) and their comparison with the whole milk replacer Kalvolak (the Netherlands) it was revealed, that indices of a daily average weight gain in calves of the first group fed with foreign milk replacer, and in calves of the second groups, which were fed with the national milk replacer, did not show authentic differences (806 and 816 g). However, the prime cost of 1kg of live weight gain in the second case was on 43% cheaper than in the first one. The cost price of 1kg of live weight gain of calves on expenses for fodder units in trial group was on 33% cheaper in comparison with the control group