The influences of certain factors of organic milk production on cow productivity

The use of animal breeds adapted to local conditions is one of the mandatory factors for the production of organic milk. Considering the mass crossing with Holstein breed carried out in recent decades, this condition should ensure the breed biodiversity and, as a result, contribute to the restoration and strengthening of the ecological balance. The potential of organic dairy farming in the Oryol region is represented by an array of black-and-white/Simmental cattle of local selection. Imported Holsteins and their mixtures are also widespread in the region. The prospect of transition of some dairy farms of the Oryol region to organic technology requires complex studies to determine the optimal dairy cattle genotypes from a zootechnical and environmental point of view. Another important aspect of the transition to the production of organic milk is the use of a certain type of feed that requires exclusion of inorganic fertilizers, plant protection products, etc., when growing them. Due to the research, we found that in a milk-producing farm that does not use chemical fertilizers and plant protection chemicals in feed cultivation, an increase in pedigree in Holstein breed does not lead to an increase in milk yields and milk fat for 305 days of lactation. On the other hand, in a farm that uses chemical fertilizers and plant protection products for growing fodder, an increase in the pedigree percentage of the Holstein breed leads to a significant increase in milk yields for 305 days of lactation, while no differences in milk fat were detected. In experimental farms, crossing with Holstein breed does not lead to a change in the bio-chemical composition of milk. Therefore, the differences between the control and experimental groups on the content of dry matter, protein and sugar in milk, as well as on the SOMO indicator, both under conditions of organic feed production and intensive animal husbandry, have not been established. In addition, Holstein milk of cows with pedigree of 50, 75 and 87.5% is characterized by a significantly lower content of casein protein in milk than analogs of the black and white breed.