Zhulinska O. Clinical and Laboratory Criteria for Monitoring and Predicting Reproductive Function in Sheep and Methods of its Stimulation

In the dissertation reproductive indicators of Ascanian selection domestic sheep breeds are presented: Karakul, Meat-Wool and Merino. The dependence on the breed and climatic features of the year indicators of fertility, fecundity, release of lambs per 100 females are presented. For the first time, data are reported: on the percentage of different breeds ewes that show signs of sexual arousal during pregnancy; the percentage of ewes with premature birth; embryonic mortality rate; percentage of ewes with extended sexual cycle. The ewes' average reproductive age of the studied species was established. In general, AscanianKarakul showed the best reproductive performance, but their average reproductive age was the shortest. The Clinical laboratory criteria for predicting reproductive function were tested based on the morphological and functional features of the sheep reproductive organs, the cervical mucus physical and biochemical properties. For the first time, a laparoscopic examination 4–6 days after insemination the peculiarities of the formation of corpus luteum in sheep and the prognostic meaning of the formations in the ovaries for fertility was established were revealed. The pedigree features of the postpartum period course and the restoration of sexual cyclicity have been determined; integrated clinical and laboratory criteria for assessing and predicting postpartum involution, fertility and diagnosis of obstetric pathology have been developed. Thus, the shortest period of postpartum involution was noted in Ascanian Karakul and Ascanian Meat-Wool ewes, long uterine secretions in Ascanian Merino ewes were observed. A method of cytovaginal research in sheep using new criteria for evaluating their vaginal smear, in particular the percentage of destroyed, non-nuclear epithelial cells, atypical cells (atrophic epithelial cells, vacuolized cytoplasm epithelial cells), as well as the ratio of various groups and subgroups of epithelial cells in smears was developed. Based on smear evaluation criteria, prognostic signs of fertility were established during sexual heat, in the first two weeks after insemination and in the postpartum period. For the first time, methods of stimulation of postpartum involution and reproductive function of sheep in the anestral season with the use of aovine placenta tissue preparation were developed and tested, its effect on sexual cyclicality, fertility and prolificacy was established.