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This experiment was conducted to determine the advantages of introducing modern innovative approaches to dairy herd management based on the study and implementation of the methodological of International Committee for Animal Recording (ICAR). This research shows the main directions for introduction to new breeding and the technological model of interaction with breeding farms for breeding dairy cattle. This interaction occurs through the services provision for breeding farms, the control-assistant and expert-boniter services, as well as laboratories for selection control of milk quality and genetic control. The tasks of the control-assistant service included participation in the control milking of cows and individual milk samples picking from each cow and its delivery to the laboratory in a chilled form. Using as the example dairy herd of the black and white breed by studying the dynamics of somatic cells has been showing the effectiveness of different methods for assessing the quality of milk. Implementation of the milk quality regular monitoring during 1-2 months allows bringing the main parameters of milk quality in line with the requirements of national and international ICAR standards. The cow's conformation assessment by animals' linear assessment allows revealing the bull’s prepotent abilities and choosing the right strategy for improving the cow's conformation in the herd. Genetic well-being assessment of cows makes it possible to exclude unwanted individuals with genetic abnormalities and use only healthy animals in breeding. The research purpose was studying the possibility of applying the ICAR method in Russian breeding livestock to improve the dairy herd management system. The research results showed that Implementation of individual veterinary measures for two months allowed reducing the average somatic cell count by 1.85 times and reaching the level recommended by ICAR. The spread of individual indicators also significantly decreased. Therefore, Using the individual monitoring of dairy raw materials quality assessment makes it possible to study the influence of para-typical (climatic) factors on the content of dairy components, as well as to stabilize the quality parameters in terms of the level of somatic cells not higher than 200 thousand cells/cm3. Keywords: Breeding, Dairy cattle breeding, Dairy herd, Genetic resources, Milk quality.

The aim of this study was to investigate the influence of the MyoD1 gene polymorphisms on some body parameters in sheep. MyoD1 polymorphisms were detected using NimbleGen sequencing tech-nology (Roche, USA). The effect of polymorphisms identified was investigated in Stavropol sheep breed rams (n=30). In coding and regulatory parts of gene 26, single nucleotide polymorphisms (SNP) were detected. These were the substitutions: c.-2112C>G, c.-1806A>G, c.-1687T>C, c.-1608C>T, c.-1603G>T, c.-1578G>A, c.-1235G>A, c.-910G>T, c.-909G>T, c.-880G>A, c.-637C>T, c.-412G>T, c.244C>T, c.246G>T, c.253G>T, c.259G>C, c.261C>T, c.269C>G, c.274C>A, c.276C>G, c.277C>A, c.279C>T, c.281C>A, c.287C>A, c.325T>C and c.483C>T. Sixteen of these SNPs have been identified for the first time. The complex of the four SNPs c.-1578, c.-880, c.-637, c.325 and c.-1235 occurred in Stavropol sheep breed only together. The study of the influence of these SNPs on the body parameters of rams showed the absence of significant correlation between their presence and the body size of the animals. The SNPs c.-910 and c.-909 were associated with improved body parameters, but they were found in a very small numbers of animals, which does not allow making definitive conclusions.

An understanding of what effects particular genes can have on body parameters in productive animals is particularly significant for the process of marker-assisted selection. The gene of transcriptional factor CCAAT/enhancer-binding protein delta (CEBPD gene) is involved in the process of growth in animals and is known to be a promising candidate for use as a genomic marker. The structure of the CEBPD gene locus was determined using NimbleGen sequencing technology (Roche, USA). The effect of polymorphisms, which were identified using the aforementioned technology, was investigated in 30 rams of the Manych Merino sheep breed. Twenty-two single nucleotide polymorphisms (SNP) were detected in the CEBPD gene locus. Significantly, two SNPs, namely, g.315TG and g.327CT, have been identified for the first time. It was demonstrated that the complex of linked SNPs, consisting of g.301AT, g.426TC, and g.1226TC, had a negligible effect on body parameters in Manych Merino sheep. Animals with the heterozygous type of SNP g.1142CT exhibited changes solely in the chest and croup width. The newly discovered SNP g.327CT was proven to have a negative effect on live weight and body size (p 0.05) in Manych Merino sheep. Sheep with the heterozygous type of g.562GA and g.3112CG SNP complex showed an increase in live weight and dimensions (p 0.05) compared with those of wild homozygous type. Consequently, SNPs g.327CT, g.562GA, and g.3112CG in the CEBPD gene locus can be successfully used as markers in sheep breeding. Future research will evaluate the influence of the aforementioned SNPs on slaughter indicators for sheep meat production.

Candidate genes associated with meat productivity often affect the performance of myostatin and muscle development in general. The MyoD1 gene is a member of the myogenic regulatory factor (MRF) family and plays a key role in the differentiation of skeletal muscle cells in vertebrates. We investigated the structure of the MyoD1 gene. The effect of polymorphisms on meat production was studied in the Russian sheep breed Manych Merino. To detect alleles, we used NimbleGen sequencing technology (Roche, USA). In the Manych Merino breed, we found 14 single nucleotide polymorphisms (SNPs) associated with substitutions, all in the second exon, namely, c.244C>T, c.246G>T, c.253G>T, c.259G>C, c.261C>T, c.269C>G, c.274C>A, c.276C>G, c.277C>A, c.279C>T, c.281C>A, c.287C>A, c.325T>C, and c.483C>T. All of these SNPs, except from c.325T>C, were detected here for the first time. The Manych Merino breed had 13 substitutions that were present as homozygous type. Only SNP c.325T>C occurred as the wild type of homozygotes and heterozygotes in the ratio 2:1. We found that SNP c.325T>C was associated with some vital body parameters, including parameters of height and croup measurement. Thus, the determination of allelic variants of the MyoD1 gene may be used in marker assisted genetic selection schemes.