Evaluación de los tratamientos de sincronización sin estradiol sobre la fertilidad en receptoras cruza cebú transferidas con embriones in vitro

The objective of this research was to evaluate the synchronization protocols with intravaginal progesterone devices in association with GnRH or estrogen on fertility, in cross-breed zebu cows receiving embryos in vitro. 60 cows were used, distributed in lots of 20 per group (Co-Synch 5, Co-Synch 6 and Conventional with estradiol cypionate or ECP, as control). The data was analyzed by means of general and mixed models in InfoStat (2020) with Logit link to determine the influence of the different variables and their interactions, with an alpha <0.05. The highest percentage of cows in heat was in the Conventional protocol (19/20 = 95%) compared to the Co-Synch protocol (17/20 = 85%); (P = 0.04). The diameter of the corpora lutea, Co-Synch 5 days (20.4 ± 1.11 mm) was greater than Co-Synch 6 days (18.4 ± 0.82 mm) and Conventional (16.81 ± 0.95 mm; P = 0.03), while the pregnancy rate was 42% in the 6-day Co-Synch cows and 39% in the Conventional one, significantly higher than the 5-day Co-Synch cows (25.0%; p <0.05). In the follicle upon removal of progesterone devices, the conventional group presented a smaller diameter (7.82 ± 0.59 mm), than Co-Synch 6 days (11.1 ± 0.05 mm) and Co-Synch 5 days 12.5 ± 0.71 mm (P = 0.03). It is concluded that the prolongation of proestrum in the Co-Synch protocol generated a similar fertility to the group of cows synchronized with the Conventional treatment with DBS as an ovulation inducer.

• 主要作者: Vargas Vera, Cruz María (author)
• 其他作者: Campozano Zambrano, Junior German (author)
• 格式: bachelorThesis
• 語言: spa
• 出版: 2021
• 主題: Transferencia de Embriones; Estradiol; Progesterona; Tasa de concepción; Dinámica folicular
• 在線閱讀: http://repositorio.espam.edu.ec/handle/42000/1622