Developments on Improving the Technology to Obtain Large Cattle Embryos of the Desired Gender in the Republic of Kazakhstan

Abstract

Objective: Development and improvement of the technology for obtaining embryos of the desired gender and determination of the rate of maturation and fertilisation of follicular oocytes of cows in various culture systems, and investigation of the effect of micromanipulation methods on viability of zygotes and embryos, obtained through in vitro fertilisation.

Methods: In vitro method, in vivo method, hormonal stimulation method, superovulation method, transvaginal puncture of ovaries, cryopreservation method, embryo transfer.

Results: Culture system serves as the main condition for maturation and further development of embryos. Studying “in vitro” fertilisation of ova with sex-sorted semen has shown that fertilisation rate of follicular oocytes is about 75%, and the percentage of development to farther stages is 52.4% or 2.2 morphologically viable embryos per a cow-donor. 5 embryos had embryonal blocks (developmental arrests), one embryo had it at the stage of two pronuclei, and four embryos – at the stage of 4-32 blastomeres.

Conclusion: These research studies, carried out in the Republic of Kazakhstan for the first time, afforded the opportunity to apply them widely to increase the large cattle breeding stock.