Evaluación de la calidad y maduración de ovocitos bovinos obtenidos de ovarios de matadero con tres presiones de vacío

Abstract

The objective of this study was to evaluate the quality and maturation of bovine oocytes aspirated from slaughterhouse ovaries with three vacuum pressures: 50 mmHg (T1), 65 mmHg (T2), 80 mmHg (T3). For each experimental group, 84 ovaries were collected, from which about 626 oocytes were recovered per group. The ovaries were transported in appropriate conditions to Laboratory. Ovaries were randomly assigned to each treatment, and follicles between 2 and 8 mm were aspirated with a vacuum pump. The recovered COCs were then categorized and only A and B were chosen. Then, 30% of them were randomly selected to perform tests of viability and progression of meiosis, and morphometric measurements. The mean number of follicles aspirated per ovary was 13.8, 11.4 and 12.0 for T1, T2, and T3 respectively. The recovery rate was statistically similar between treatments. The percentage of class A and B oocytes was significantly greater in T1 (88.6%) and T2 (85.5%) than in T3 (80.4%, P <0.05), whereas viability did not vary between vacuum pressures. A greater proportion of oocytes from T1 (52.5%, P <0.05) than T2 (49.4%) and T3 (45.2) completed meiosis. Irrespectively of the vacuum used, there was a significant reduction of the morphometric values after the oocytes completed the maturation process. Likewise. In conclusion, the vacuum used to obtain bovine oocytes from slaughterhouse ovaries affected some functional characteristics and the morphometric variables studied.