УДК 636.2.082.32
Autors:
Kharlap S. Yu., Candidate of Biological Sciences, Associate Professor
Gorelik O. V., Doctor of Agricultural Sciences, Professor
Neverova O. P., Candidate of Biological Sciences, Associate Professor
Ural State Agrarian University
Gorelik A. S., Candidate of Biological Sciences, Associate Professor
Ural Institute of GPS of the Ministry of Emergency Situations of Russia
Summary In the Russian Federation, Holstein cattle of various domestic breeding in different regions are bred. These animals differ from each other in terms of economic-useful and economic-biological characteristics, which is explained by the natural-climatic, ecological-fodder conditions and breed resources used in their breeding. In this regard, the study of economic and useful signs of dairy cattle of the Holstein breed is relevant and of practical importance. The purpose of the work was to assess the economic and useful signs of modern dairy cattle of the Holstein breed, taking into account the age in lactation. A natural change in the lactation activity of cows with a change in age is traced, namely, an increase in yield until full-age lactation is achieved and then a slow decrease in them. Since the difference in yield was insignificant and unreliable, we can conclude that the yield was stabilized up to 7 lactation inclusive. The highest productivity indicators in cows were for the third lactation both for the entire lactation and for 305 days of lactation. Starting from the fourth lactation, a decrease in yields of 0.3 (5 lactation) to 8.5% (8 lactation) is observed. The average daily impact for lactation is lower than the average daily impact for lactation by 0.1-1.8 kg or 0.6- 11.1%, that is, due to an increase in the duration of lactation, there is a decrease in the average daily impact with the course of lactation activity and at the end of lactation they turn out to be low. According to the MJ in milk, it is noted that regardless of age, it exceeds the requirements of the standard. There is an increase in this indicator with age, which can be explained as growing up animals and improving metabolism.
Keywords: cattle, cows, age, lactation, oud, MJ and MDB in milk.
