FACTORS INFLUENCE ON THE MILK QUALITY INDICATORS OF NOVOOLEKSANDRIVSKIA HEAVY-DUTY BREED MARES

The article presents the results of studies of milk productivity and milk quality of mares of the Novooleksandrivka heavy draft breed. The daily milk yield of mares and milk quality indicators in samples taken in June and August were determined, and it was proven that all indicators vary significantly. It was established that the indicators of dry matter, protein, lactose and dry non-fat milk residue were higher in June, and the protein content, fat-protein ratio, freezing point and somatic cell count were higher in August. Differences in milk quality indicators from the first and second milking were revealed, and a higher content of almost all studied indicators was established in milk samples taken from the first milking in June and August, in August – with a much smaller difference. Significant correlations were found between milk quality indicators – dry matter (r=0.856), fat (r=0.728), fat-protein ratio (r=0.861) in milk samples taken in June and August from the first, second milking and daily milk yield. In milk milked in August, these relationships. In all samples, a negative relationship was established between the amount of milk and the content of somatic cells. The influence of the lactation period on milk productivity and milk quality indicators of experimental mares was established – the highest daily milk yield, dry matter and fat content in milk were characterized by mares at the lowest lactation periods. The influence of the age of experimental mares on their daily milk yield and milk quality indicators was established, the superiority of mares aged 9-13 years in June (r=0.431), and older ones in August (r=0.352) was proven in terms of daily milk yield. It was determined that the age of mares affects the duration of their foaling (r=0.396). The advantage in daily milk yield of mares with a foaling duration of over 350 days was proven according to the results of control milking in both June and August. In terms of dry matter, fat and fat-protein ratio in milk samples of experimental mares with a foaling duration of over 340 days according to the results of control milking in both June and August, as well as the highest lactose content and freezing point index in samples taken in June and protein – in samples taken in August. It was established that mares that foaled with foals, with a high degree of probability (p˂0.01) had a higher daily milk yield, as well as milk yields for the first and second milking, a higher dry matter, fat, fat-protein ratio.