کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
10891585 1082050 2016 19 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Role of cumulus cells during vitrification and fertilization of mature bovine oocytes: Effects on survival, fertilization, and blastocyst development
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک علوم دامی و جانورشناسی
پیش نمایش صفحه اول مقاله
Role of cumulus cells during vitrification and fertilization of mature bovine oocytes: Effects on survival, fertilization, and blastocyst development
چکیده انگلیسی
This study was designed to determine the role of cumulus cells during vitrification of bovine oocytes. Mature cumulus-oocyte complexes (COCs) with many layers of cumulus cells, corona radiata oocytes (CRs), with a few layers of cumulus cells, and denuded oocytes (DOs) without cumulus cells were vitrified in 15% ethylene glycol, 15% dimethyl sulfoxide, and 0.5-M sucrose. Oocytes that survived the vitrification process were fertilized. Denuded oocytes were fertilized with or without supplementation of intact COCs (DOsCOCs). First, survival and embryo development rates were studied. Higher survival rates were obtained for DOs and DOsCOCs (94% and 95%, respectively) compared with COCs (82.7%, P < 0.05). Corona radiata oocytes showed similar survival rates when compared with DOs. The cleavage and blastocyst rates of vitrified DOs were compromised because cumulus cells were not present during the fertilization (34% and 2.7%, respectively). However, the situation could be reverted when DOs were supplemented with intact COCs (DOsCOCs; 62.7% and 12.7%, respectively, P < 0.05). Vitrified CRs showed similar cleavage and blastocyst rate (49.3% and 7.7%, respectively) compared with COCs (54.8% and 4.9%, respectively). In the second experiment, the penetration rate was analyzed. Removing cumulus cells before fertilization reduced the fertilization of vitrified DOs compared with COCs (24.3% vs. 52.8%, P < 0.05). The supplementation of DOs with intact COCs (DOsCOCs) improved the fertilization rate though (49.6%, P < 0.05). No differences in the fertilization rate were found between CRs and COCs. In the third experiment, parthenogenetic activation was examined. Interestingly, the CRs group showed higher cleavage and blastocyst rates (76.8% and 29.6%, respectively) than the COCs (39.1% and 7.5%, respectively, P < 0.05). Furthermore, oocytes from vitrified CRs had the same odds to become a blastocyst as fresh oocytes (1.1 vs. 1.5, respectively). In conclusion, our data reported that cumulus cells reduce survival after the vitrification of mature bovine oocytes. Because cumulus cells are required for fertilization, the use of partially DOs (CRs) or the addition of intact COCs (DOsCOCs) during fertilization can result in higher survival and embryo development after vitrification.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Theriogenology - Volume 86, Issue 2, 15 July 2016, Pages 635-641
نویسندگان
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