Innovative technologies of dairy cattle reproduction

Abstract

The American company for the reproduction of dairy cattle – World Wide Sires was formed in 1976 in the United States, and its subsidiary World Wide Sires Russia – in 2006 in the Russian Federation. Over the past decades the average milk yield of cows has been increased significantly, but their fertility has been decreased. A comparison of the DNA of cows producing about 20,000 kg of milk and more than 1,000 kg of milk fat per lactation has shown a genetic association between the milk yield of cows and the fertility of breeding sires. Therefore, one of the directions of the company’s development is the development of innovative technologies for improving reproduction with the genetic improvement of breeding traits of breeding sires. Improving the fertility of Holstein sires and their high-quality semen are the main conditions for solving problems related to the reproductive function of animals. Application of index selection programs, including OptiFeed (optimal feeding), Production-max (best production), Fertility (high reproduction capacity), etc. are powerful lever of herd management. All available genetic indexes are directly or indirectly included in the general index of breeding value of the sire – TPI. One of the methods of refining the index system is the use of ultrasexed semen with 4 million sperm cells in a dose, which increases fertilization in heifers and cows by 5 and 6 %, respectively. Another method of refi ning the index system was the definition of inbreeding. For example, an increase in inbreeding by 1 % led to a decrease in the dollar profit index NM$ by 24 points, added 36 undesirable days to the age of the first calving, reduced productive life by 13 days, reduced milk yield by an average of 358 kg of milk and 11,3 kg of milk protein per lactation. The cost of each additional day of the open days’ period after the start of the hunt ranged from 220 to 370 rubles loss per 1 cow per year.