Rivera R M, Al-Katanani Y M, Paula-Lopes F F, Hansen P J
Department of Dairy and Poultry Sciences, University of Florida, Gainesville 32611-0920, USA.
J Dairy Sci. 2000 Feb;83(2):305-7. doi: 10.3168/jds.S0022-0302(00)74879-X.
The objective of this study was to determine if season affected the production of in vitro-derived bovine embryos from oocytes of cattle in a subtropical environment. Ovaries (approximately 75% beef cattle, including many with Bos indicus breeding) were collected from an abattoir. Oocytes were obtained and subjected to in vitro maturation and fertilization. Embryos were then cultured in CR1aa medium. Cleavage rate averaged 72.2+/-9.7% and was not different between months of collection. In addition, no differences were observed in the percent of oocytes or embryos that became blastocysts on d 8 or 9 after insemination. Least-squares means averaged across months for percent oocytes and cleaved embryos to blastocyst on d 8 were 22.8+/-7.5% and 31.2+/-9.4%, respectively. When d 8 blastocysts were classified according to stage of development (nonexpanded, expanded, and hatched), an effect of month was observed that reflected month-to-month variation and not a consistent change associated with season. Taken together, results failed to indicate an effect of season on in vitro production of embryos in a subtropical environment.
本研究的目的是确定季节是否会影响亚热带环境中牛卵巢卵母细胞体外培养牛胚胎的产量。卵巢（约75%为肉牛，包括许多具有印度瘤牛血统的牛）从屠宰场采集。获取卵母细胞并进行体外成熟和受精。然后将胚胎在CR1aa培养基中培养。平均卵裂率为72.2±9.7%，不同采集月份之间无差异。此外，在授精后第8天或第9天发育为囊胚的卵母细胞或胚胎百分比方面未观察到差异。各月份卵母细胞和第8天发育为囊胚的卵裂胚胎百分比的最小二乘均值分别为22.8±7.5%和31.2±9.4%。当根据发育阶段（未扩张、扩张和孵化）对第8天的囊胚进行分类时，观察到月份的影响，这反映了逐月变化，而非与季节相关的一致变化。综合来看，结果未能表明季节对亚热带环境中胚胎体外生产有影响。
