RESUMEN
The pregnancy rate following embryo transfer (ET) is a very important factor in the success of embryo production programs. Different strategies were therefore developed to increase pregnancy rates. The aim of this meta-analysis was to investigate the effects of hormone treatments used to increase the success of embryo transfer programs on pregnancy rates. A meta-analysis was performed of 46 trials from 39 publications involving treated (n = 7856) and control (n = 6663) cattle. The meta-analysis explained the effect size with its 95 % confidence interval (CI) for pregnancy per embryo transfer (P/ET) after hormonal treatment under different moderators. Hormonal support was found to increase P/ET compared to the control group (P < 0.05). However, GnRH treatment was found to increase P/ET by approximately 4.3 % and hCG treatment by 8.0 %. Progesterone supplementation was not found to have a statistically significant effect on P/ET. In addition, GnRH treatment significantly increased P/ET when used to transfer in vitro or frozen-thawed embryos or in studies using cows as recipients. It was observed that hCG treatment had a positive effect on P/ET according to all moderators. Progesterone supplementation significantly increased P/ET when frozen embryos were transferred and reduced P/ET, especially in publications where fresh or in vitro produced embryos were transferred or cows were used as recipients. The results of this meta-analysis showed that the use of GnRH, and hCG, in bovine embryo transfer programs increased P/ET, whereas the use of progesterone had no effect on P/ET. However, it was found that P/ET could increase/decrease depending on the moderator.
Asunto(s)
Transferencia de Embrión , Progesterona , Animales , Bovinos , Femenino , Embarazo , Transferencia de Embrión/veterinaria , Transferencia de Embrión/métodos , Fertilidad , Hormona Liberadora de Gonadotropina/farmacología , Índice de Embarazo , Progesterona/metabolismoRESUMEN
This study aimed to investigate the effect of putrescine supplementation to maturation medium during in vitro embryo production in cattle on maturation and embryo development/quality. Oocytes obtained from the ovaries of Holstein cattle were used in the study. Obtained cumulus-oocyte complexes were evaluated according to morphological structure, cytoplasmic features, and cumulus cell number, and only Category-I ones were used in the study. Before the in vitro maturation step, oocytes were randomly divided into two groups. In the first group (Putrescine group, n = 159), 0.5 mM putrescine was added to the maturation medium before in vitro maturation. No addition was applied to the maturation medium of the second group (Control group, n = 149). Cumulus expansion degrees of oocytes following maturation (Grade I: poor, Grade II: partial, and Grade III: complete) were determined. In addition, the meiosis of oocytes after maturation was evaluated by differential staining. Then the oocytes were left for fertilization with sperm and finally, possible zygotes were transferred to the culture medium. After determining the developmental stages and quality of the embryos after in vitro culture, only the embryos at the blastocyst stage were stained with the differential staining method to determine the cell numbers. When the cumulus expansion degrees of the groups were evaluated, the Grade III cumulus expansion rate in the putrescine group was higher than the control group (74.21% and 60.4%; respectively) and the Grade I expansion rate (11.95% and 26.17%; respectively) was found lower (p < .05). When the resumption of meiosis was evaluated according to the cumulus expansion degrees, it was determined that the rate of resumption of meiosis increased as the cumulus expansion increased. In addition, the cleavage rates of oocytes and reaching the blastocyst in the putrescine group were found to be higher than in the control group (p < .05). Moreover, inner cell mass, trophectoderm cells, and total cell counts were found to be higher in blastocysts obtained after the putrescine supplementation to the maturation medium compared to the control group (p < .05). As a result, it was determined that the putrescine supplementation to the maturation medium during in vitro embryo production in cattle increased the degree of cumulus expansion and the rate of resumption of meiosis. In addition, putrescine supplementation was thought to increase the rate of reaching the blastocyst of oocytes due to better cell development in embryos.
Asunto(s)
Putrescina , Semen , Masculino , Femenino , Bovinos , Animales , Putrescina/farmacología , Oocitos , Desarrollo Embrionario , Blastocisto , Suplementos Dietéticos , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Técnicas de Maduración In Vitro de los Oocitos/métodos , Fertilización In Vitro/veterinaria , Células del CúmuloRESUMEN
This study aimed to determine the effect of microfluidic sperm sorting chip on embryo development and quality in the sperm treatment step in in vitro embryo production in cattle. Only A-quality oocytes obtained from the ovaries of Holstein cattle were included in the study. These oocytes were first placed in in vitro maturation medium, and matured oocytes were randomly divided into two groups at the 24th hour of maturation. Oocytes in the first group with the Microfluidic Sperm Sorting Chip (MFSC, n = 154) were put into a fertilization medium with spermatozoa prepared with microfluidic sperm sorting device. Oocytes in the second group (Con, n = 169) were fertilized with spermatozoa prepared by the routine sperm treatment step of the commercial company. The rate of cleavage (85.71% vs. 76.33%, respectively) and of reaching the blastocyst (44.15% vs. 32.54%, respectively) in the MFSC group were higher than the control group. In addition, it was determined that the numbers of ICM (45.8 ± 2.04 vs. 39.2 ± 1.85, respectively), TE (122.13 ± 2.19 vs. 115.0 ± 2.61, respectively), TC (167.93 ± 2.89 vs. 154.2 ± 2.62, respectively) increased in the MFSC group compared to the control group. A statistically significant difference was found in the number of cells with apoptosis per embryo (5.14 ± 0.77 vs. 11.91 ± 0.79) and apoptotic index rates (3.06 ± 0.47 vs. 7.72 ± 0.55%) of the MFSC and Con groups. As a result, we concluded that using microfluidic sperm sorting chips during sperm treatment in bovine IVEP increases the rate of reaching the blastocyst, embryo development, and quality and reduces the possibility of apoptosis in developing blastocysts. For this reason, it is also thought that the use of microfluidic sperm sorting devices during sperm treatment in bovine IVEP may be a new alternative in this field.