tailieunhanh - Báo cáo khoa học: "Thickness of cumulus cell layer is a significant factor in meiotic competence of buffalo oocytes"

Tuyển tập các báo cáo nghiên cứu khoa học quốc tế về bệnh thú y đề tài: Thickness of cumulus cell layer is a significant factor in meiotic competence of buffalo oocytes | J. Vet. Sci. 2004 5 3 247-251 JOURNAL OF Veterinary Science Thickness of cumulus cell layer is a significant factor in meiotic competence of buffalo oocytes Hassan M. Warriach1 Kazim R. Chohan2 1 Department of Theriogenology Faculty of Veterinary Sciences University of Veterinary and Animal Sciences Lahore 54000 Pakistan Undrology andIVFLaboratories School of Medicine University of Utah 675 Arapeen Drive Suite 205 Salt Lake City UT 84108 USA This study evaluated the meiotic competence of buffalo oocytes with different layers of cumulus cells. A total of 588 oocytes were collected from 775 ovaries averaging oocytes per ovary. Oocytes with homogenous cytoplasm n 441 were selected for in vitro maturation IVM and divided into four groups based on their cumulus morphology a oocytes with 3 layers of cumulus cells b 1-2 layers of cumulus cells and oocytes with partial remnants or no cumulus cells to be cocultured c with or d without cumulus cells. Oocytes in all four groups were matured in 100 pL drop of TCM-199 supplemented with 10 pg mL follicle stimulating hormone FSH 10 pg mL luteinizing hormone LH pg mL estradiol 75 pg mL streptomycin 100 IU mL penicillin 10 mM Hepes and 10 FBS at 39oC and 5 CO2 for 24 hours. After IVM cumulus cells were removed from oocytes using 3 mg mL hyaluronidase fixed in 3 glutaraldehyde stained with DAPI and evaluated for meiotic competence. The oocytes with 3 layers of cumulus cells showed higher maturation rates p than oocytes with partial or no cumulus cells and oocytes co-cultured with cumulus cells but did not differ from oocytes having 1-2 layers of cumulus cells . The degeneration rates were higher p for oocytes with partial or no cumulus cells 51 than rest of the groups range to . These results suggest that buffalo oocytes with intact layers of cumulus cells show better IVM rates than oocytes without cumulus cells and the co-culture of poor quality oocytes with cumulus cells improves .