Application of sexed semen of sires in breeding farms of Kaluga region

Abstract

Relevance. The main direction in the improvement of dairy cattle breeds is the search for ways and methods of creating highly productive herds. However, the successful solution of these issues is impossible without the use of modern methods and technologies. Among them, sexed sperm is a sperm divided into Xand Y-containing spermatozoa. When using sexed sperm in dairy cattle breeding, it is possible to regulate the receipt of the desired sex (heifers). The effective use of sexed semen will provide farms with a complete set of their own breeding stock and will allow the sale of heifers.Methods. The object of research was cows inseminated with sexed sperm of stud bulls of different breeds in a breeding unit. The fertilization of the breeding stock, the duration of pregnancy, the effect of the season on fertilization, analytic investigation of calf crop percent were investigated. For analysis the data were used from the database for zootechnical and pedigree data registration «SELEKS».Results It was found that the fertilization of heifers from the first insemination with sexed sperm was 38,8%, subsequently it decreased and amounted to 27,7% at the second insemination, 5,5% at the third. 28% remained infertile, 72% of heifers from the total remained pregnant. 85% of live heifers and 15% of bulls were obtained. During the initial insemination of cows of the first calving with sexed sperm, 27,7% of cows became pregnant, with repeated insemination — 27,7%. Fertilization decreased, 39,1% of the animals remained infertile. The best results of fertilization of breeding stock using sexed semen were obtained during the primary insemination of heifers