Artificial regulation of the efficiency of embryo production in culture IN VITRO

The paper presents the results of studies on the effect of exogenous regulation of folliculogenesis on the efficiency of obtaining embryos in culture in vitro. The research was carried out within the framework of the state program of scientific research "Scienceintensive technologies and equipment for 2016-2020" (subprogram 1 "Innovative biotechnology-2020"). The research was carried out on the basis of the branch biotechnological laboratory for the reproduction of farm animals of the EE "Grodno State Agrarian University". It was found that the number of aspirated follicles per aspiration increased in stimulated animals compared to the control group by 19.2-39.7%. The number of oocytes suitable for staging for maturation increased only in the groups treated with FSHsuper at a dose of 12.5 and 50 Arm units by 4.1 and 3.4 p.p., respectively. The crushing rate was also lower in the control group by 2.2-6.6%. In terms of embryo yield, calculated on the basis of the number of fertilized oocytes, the control group was slightly better - by 2.3-2.6 p.p. or 25.5% vs. 20.9%, 23.2% and 23.2% when using 12.5, 25 and 50 arm units, respectively. When donors were stimulated with the hormonal preparation Pluset, by the number of aspirated follicles, the difference in favor of the experimental groups was 4.6-68.7%, by the yield of suitable cells the indices were somewhat equalized and the advantage of the experimental groups was only 1.4-7.8 p.p. The control group exceeded the experimental groups by 1-7-10.0 p.p. in the number of crushed embryos. Embryo yield in the control group was 21.7% versus 24.4% in group 1, 22.9% in group 2, and 18.0% in group 3. Removal of follicles greater than 6 mm reduced the number of aspirated follicles by 33.7%, increased the yield of usable cells by 4.7 p.p. and the embryo yield from the number of fertilized oocytes by 3.1 p.p. Removal of the dominant follicle increased the number of aspirated follicles by 40.9% the yield of viable oocytes by 5.2 p.p., the crushing rate by 7.8 p.p. and the embryo yield by 5.0 p.p.

The data obtained are of practical significance for the development of the technology of obtaining embryos in vitro, the use of which will accelerate the breeding process and improve the efficiency of selection and breeding work in cattle breeding in general.

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