Vol. 9, Issue 2, Part L (2024)

Author(s): Jainik Prajapati, VS Suthar, Rutvij Patel, MM Mansuri, Ankur Sharma, Dhwani Jhala, Sanman Samova, Madhavi Joshi and CG Joshi

Abstract: Assisted reproductive techniques, such as in vitro embryo production (IVEP), have garnered significant attention due to the slow reproductive rates observed in buffaloes. The aim of this study was to assess cleavage, blastocyst formation, and hatching rates in ovarian cumulus oocyte complexes (COCs) obtained from slaughtered buffaloes. COCs were recovered from buffalo ovarian follicles using the aspiration method. A total of 655 ovaries were collected and utilized across 29 sessions (averaging 23±1.2 ovaries per session). Surface follicles were measured with a Vernier caliper and classified into three groups based on diameter: < 3 mm, 3-5 mm, and > 5 mm. These follicles were then subjected to in vitro maturation (IVM), in vitro fertilization (IVF), and in vitro culture (IVC) using frozen semen doses. The maturation of COCs of grades I to IV was evaluated based on morphological characteristics 22 hours after IVM. Cleavage, blastocyst formation, and hatching rates were assessed 72 hours, 6 days, and 6 to 9 days after IVC, respectively. Overall, 55.15% (1387) of follicles were small, 39.05% (982) were medium-sized, and 5.80% (146) were large. A total of 66.76% (1679/2515) COCs were recovered from these follicles. The distribution of COC grades was as follows: 36.09% (I), 36.21% (II), 24.66% (III), and 3.04% (IV). Out of 1640 presumptive zygotes, 1015 successfully cleaved, resulting in a cleavage rate of 63.1%. Of these, 295 (20%) reached the blastocyst stage by day 6. Among the blastocysts, 131 were observed for hatching, with 63 (48.1%) hatching between the 6th and 8th day post IVC. In conclusion, the study suggests that IVEP could be a valuable tool for salvaging the genetic potential of the buffalo population.