In the conditions of the Republic of Belarus there was realized a complex evaluation of producer bulls of different genotypes of origin for the further correction and breeding in different categories of agricultural enterprises. In course of the study there was conducted a preliminary (without quality evaluation of daughters) estimation of bulls which gave a precise performance of each bull, made it possible to correct its type and direction of breeding. Research made it possible to considerably increase the genetic trend in accordance with indexes of milk productivity which would make it possible to form a regional type of black-and-white cattle with the given indexes of productivity and reproduction. In course of the study there were analyzed the following breeds: black-and-white, Holstein, Hungarian breeding, Swedish breeding. Comparative evaluation of reproductive qualities of bulls in accordance with age-specific and breed types was presented. Body conformations of bulls of Holsten and Black-and-white of different ae-specific groups were stated. Results of complex evaluation of full-grown, under 5 year-old and replacement producing bulls of Holstein and Black-and-white breeds were presented.

Growth and development of mixed bred Charollais x white-and-black young stock and black-and-white bull-calves since 8-month old age till and 15-month old age were studied in the conditions in the Republic of Belarus. In course of studied there were analyzed linear growth; young stock growth intensity; forage consumption; efficiency of experimental results. On the basis of obtained data there was determined the absolute growth rate of bull-calves at certain growing periods. Research results showed that dramatic changing of technology of management and feeding of mixed bred Charollais x white-and-black young stock bulls after weaning period caused the decrease of daily average live weight gain from 8-month old age till and 15-month old age in comparison with white-and-black cattle on 99 grams or 14%. Analysis of exterior of experimental animals confirmed the priority of mixed bred young cattle over white-and-black herdmates. They were characterized by massive corpus, wider and deeper barrel, wide withers, back and coupling

The Republican Agricultural Breeding Unitary Enterprise Zarechje of the Republic of Belarus is the basic horse-breeding enterprise of Belarusian coach horse breeding. In the enterprise there are 27 mares and 2 studhorses; all animals are purebred. It is established, that unaltered male horses and mares belong to Belarus coaching breed, all pedigree animals have a high class: 15 horses belong to an elite class that makes 75% from all herd, 4 heads concern the first class (20%), and 1 head – to the second class (5%). Measurements surpass the standard that can prove the appropriate selection and breeding work in the enterprise. After studying the measurements of studhorses of the enterprise in comparison with the standard it was established, that the height at crest of stallions on the average exceeds the breed standard on 30%, slanting length of a trunk - on 5,0%, a breast grasp - on 4,0% and a metacarpus grasp - on 6%. For improvement of herd of horses it is necessary to organize correctly a coupling campaign with drawing up of the coupling plan and selection of a uterus to stallions; to use in copulation only the best elite stallion.

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%.

The analysis of data on a complex of reproductive qualities crossing sows has shown, that the combinations used in the classical scheme of variable crossing have appeared are less effective in comparison with the combinations including foreign meat breeds. It is recommended to change the traditional scheme of variable crossing, having excluded from it the Belarus black-motley breed and having entered foreign breeds of L and D and also to use hybrid male pigs (D x P)