动物造模 z-bio 2022-08-09 507

　　Objective To analyze the effects of mouse strain, embryo transfer method and transfer quantity on embryo transfer results, so as to further optimize and improve embryo transfer efficiency.

　　Methods The embryos of 277 genetically modified mouse strains were obtained by superovulation and in vitro fertilization, and different numbers of embryos were transferred into the unilateral or bilateral fallopian tubes of pseudopregnant female mice. Effects of different transplantation methods on litter size and litter rate.

　　Results The litter size (4.61 ± 1.92) and the litter rate [(19.21 ± 9.70)%] of the strain group with IVF rate between 0% and 39% were significantly lower than those of other groups (all P<0.01). IVF Compared with the 90%-100% group, the litter rate in the 60%-69% group was significantly higher (P<0.05). When the number of transferred embryos was small (5), the recipient female mice were able to become pregnant, but the litter size was small, and it was easy to eat offspring. When the number of transferred embryos was more than 10, the litter size and litter rate were higher in each group. Among them, when the number of embryos transferred was about 15, the farrowing rate was the highest, reaching (46.67 ± 11.56)%, which was significantly higher than that of other groups (all P<0.01), indicating that the utilization rate of embryos was the highest at this time; when the number of embryos transferred reached 25 , the average litter size (9.67 ± 1.53) was the most, significantly higher than other groups (all P<0.01); after="" the="" number="" of="" transferred="" embryos="" increased="" to="" litter="" size="" 8.33="" 27.33="" p="">0.05).

　　Conclusions Mouse strains with in vitro fertilization rates below 40% have lower average litter size and litter size. When the number of transferred embryos was about 15, the utilization rate of embryos was the largest; when the number of transferred embryos was about 25, the litter size was the largest. There was no significant difference in litter size and litter rate between unilateral and bilateral transplants.