INDUCTION OF SUPEROVULATION IN BEIGE-COLORED KARAKUL SHEEP FOR EMBRYO TRANSPLANTATION

Abstract

This study provides a reasoned justification for the conservation of genetic resources of beige-colored Karakul sheep and develops a method for accelerated reproduction and effective preservation of high-value Karakul genotypes, particularly those with rare beige coat colors, through repeated embryo recovery from donor ewes. The method involves detecting estrus, administering pregnant mare serum (PMS) gonadotropin at a dose of 26 IU/kg body weight on days 13-14 of the estrous cycle, mating ewes with rams of the corresponding coat color upon estrus onset, and subsequent embryo collection. To increase the number of recovered embryos, donor ewes are additionally treated with PMS gonadotropin at the same dose on days 14-16 of the estrous cycle, following a surgical procedure and an 18-22 day interval. Subsequent technological procedures include estrus detection, mating, and embryo flushing.

Application of this method allows the recovery of, on average, 3.1 additional embryos per high-quality donor from ewes with rare coat colors compared to conventional methods. This indicates the feasibility of using the same donors twice within a single breeding season as embryo producers. Repeated embryo recovery from the same donors in practical breeding programs represents an additional resource for addressing both theoretical and applied challenges in the conservation and propagation of beige-colored Karakul sheep.