Use of gonadotropins on females of agricultural species with year-round and seasonal type of reproduction

In this work we determined the efficiency of induction of superovulation and folliculogenesis in females of agricultural species with low- and multiple-fetal type of pregnancy, as well as with seasonal and year-round manifestation of estrus, by different modes of FSH-super preparation administration. For the first time studies on the use of pituitary gonadotropins on females with different types of reproduction for the induction of superovulation, folliculogenesis and ovulation in different seasons of the year were conducted. Superovulation induction was performed in embryo donor cows of specialized and aboriginal breeds and different directions of productivity during the year under the same housing conditions. Induction of folliculogenesis was carried out in female domestic rabbits when kept in shelters and vivariums during the year and in female American mink when kept in shelters and vivariums, both in the season of reproduction and outside the season of sexual activity. When using single injection regimens of FSH-super in combination with prolongers polyvinyl alcohol and polyethylene glycol, the response of embryo donor cows and female rabbits is more effective compared to the classical protocol with multiple injections. It was also revealed that cows of the aboriginal Kalmyk breed respond to the administration of gonadotropins for superovulation induction only during their reproductive period in summer and early fall. Rabbits during the year gave a stable positive effect on the introduction of gonadotropins when kept in the vivarium, while the level of response decreased in some months when kept in shepherds. Female American minks under vivarium conditions responded to the administration of FSH-super both in the season of reproduction and outside the season of sexual activity, in contrast to animals kept in shelters. It was found that the effectiveness of gonadotropic stimulation of females for the purpose of superovulation induction depends on the mode of drug administration and environmental factors. Administration of FSH-super with prolongers to mink and keeping in vivarium conditions contributes to overcoming the factors of seasonal variability of reproduction, which may be essential for the development of embryotransplantation methods in animals with seasonal type of reproduction with desirable phenotypic characteristics.