RESEARCH OF THE QUALITATIVE COMPOSITION OF MILK OF COWS OF SIMMENTAL BREED

Abstract

Modern dairy breeds of cattle have high milk yields. This is especially true of breeds created using Holstein breed [14]. At the same time, scientists have repeatedly stated that the use of Holstein breeders deteriorates the quality characteristics of milk productivity. Therefore, the influence of conditional blood by Holstein breed significantly affects productivity. However, researchers emphasize that the breed as a genetic factor has a significant impact on milk productivity. This explains the influence of the biochemical composition of milk on the profitability of the dairy industry. Dairy breeds that have been created in Ukraine over the past twenty years are characterized by a sufficient level of milk yield and quality indicators. The level of milk yield of animals is more than 7.0 thousand kg of milk with fat and protein content in milk above 3.8% and 3.2%, respectively. Some breeds, which are created on the basis of domestic combined breeds are characterized by a sufficient level of milk components. Their fat content in milk is more than 4.0%, and protein – more than 3.4%. During lactation, the content of milk components changes. The aim of our work was to investigate some indicators of the biochemical composition of milk of Simmental cows. Materials and methods. The research was conducted on Simmental cows kept in the Mykhailivka PZ of the Lebedyn District of the Sumy Region (n = 46) and the Urozhay SFG of the Romensky District of the Sumy Region (n = 30). For sampling of milk used counter – indicator IU-1. The milk sample was stored in a plastic container (25 ml) during the day at a temperature of +3C0, using the preservative chrompic. The content of fat and protein in milk was determined in the laboratory of Sumy National Agrarian University on the equipment Ultrasonic milk analyzer Master Classic manufacturer Milkotester Ltd (Bulgaria). The results of the research were processed by the methods of mathematical statistics using the "Statistica-6.1" package in the Windows environment on a PC. The animals fully meet the requirements of the breed standard for both the first (standard 2700 kg) and the third lactation (3500 kg). In terms of milk yield, Simmental cows met the requirements of the breed standard for both the first and second lactations. Biochemical analysis of milk was carried out to determine the level of such indicators as fat, protein, lactose, dry matter and dry nonfat milk residue. According to all the studied features, the first-born were inferior to adult animals. A statistically significant difference was found between the fat and protein content of milk in favor of adult animals. As a result, it can be argued that there is a significant difference in the amount of dry matter and dry skim milk residue between animals of different ages. Adult animals met the breed standard in terms of both fat and protein content, the first-born animals were slightly lower than the standard in terms of protein content. There are relationships of different directions and magnitudes between the contents of individual components. Statistically significant correlation coefficients were found between the content of: fat and protein; fat and dry matter; protein and dry matter; protein and skimmed milk powder. Conclusions. As a result of research, it was found that both first-born and adult Simmental cows are characterized by a sufficient level of milk productivity with high quality milk. In all respects, they met the requirements regulated by the breed standard, with the exception of the first in terms of protein content. There is a significant positive correlation between individual indicators (0.75 ± 0.03–0.96 ± 0.01).