EFFECT OF ADDITION OF FOLLICULAR FLUID, OVIDUCTAL OR GRANULOSE CELL CO-CULTURE ON CLEAVAGE AND EMBRYONIC DEVELOPMENT OF BUFFALO OOCYTES

Document Type : Original Article

Author

Department of Theriogenology, Faculty of Veterinary Medicine, Cairo University

Abstract

  The present study was undertaken with aim to study the role of addition of follicular fluid, oviductal cell and granulose co-culture on cleavage and embryonic development of buffalo oocytes. Cumulus oocyte complexes (COCs) were obtained from slaughterhouse ovaries by aspiration method. Oocytes were cultured for in vitro maturation in TCM-199 plus 10%fetal calf serum (FCS) for 24h in CO₂ incubator. Oocytes were fertilized with frozen-thawed semen capacitated in Brackett and Oliphant (BO) medium contained heparin and caffeine. After 5h of co-incubation, sperm attached matured oocyte were transferred to maturation media drops for further development and co-culture according to experimental design, Group 1 without co-culture (control), group 2 (Bovine oviductal epithelial cells, BOECs) and group3 (Granulose cells GCs). In another group of experiments, matured oocytes were fertilized with frozen-thawed semen capacitated in BO medium contained 20% Buffalo follicular fluid (BFF) then transferred to maturation media drops for further development. Oocytes were observed for cleavage after 48h of fertilization. The cleavage rate and the frequency of morula and blastocyst were recorded. Results revealed that, addition of BOECS to the culture media produced significantly (p<0.05) higher cleavage and embryonic developmental rates (Morula and blastocyst) compared to control group (35.0, 15.0 vs 10.0, 10.0%, respectively). Morula and blastocyst production rates were significantly higher in TCM- 199+10% FCS+GCs than those obtained in TCM-199+10%FCS (33.34, 13.34 vs 10.00, 0.0%; p<0.05, respectively). However, the cleavage rates were similar in both groups. The fertilization of oocytes with semen capacitated in BO medium contained 20% BFF were resulted in significantly (p<0.05) higher embryo developmental rates (Morula and blastocyst) compared with the use of heparin and caffeine in the same medium (22.23, 10.0 vs. 10.0, 0.0%, respectively). In conclusion, oviductal or granulose cell co-culture had a marked effect on cleavage and embryonic development of buffalo oocytes. Also, addition of buffalo follicular fluid to BO medium could increase the percentage of morula and blastocyst.

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