Brown B W, Radziewic T
CSIRO Divisionof Animal Production, Delivery Center, Blackstown, NSW, Australia.
Theriogenology. 1998 Jun;49(8):1525-36. doi: 10.1016/s0093-691x(98)00098-3.
An in vitro culture system for producing ovine embryos is described, in which heat inactivated sheep serum was used as a protein source for maturation, fertilization and 7-d culture phases. Ovaries obtained from a commercial abattoir were used as the source of mature ewe (285) and lamb oocytes (356), which were subsequently cultured in this system to yield similar mean cleavage rates of 91 and 92%, respectively, but significantly different (P < 0.025) proportions for blastocysts/cleaved oocytes (46 and 18%). At Days 7 or 8 of culture, embryos from each source were transferred, either singly (ewe-derived) or in pairs (ewe- and lamb-derived), to hormonally synchronized recipient ewes, resulting in the birth of lambs ranging in weight from 2.5 to 8.8 kg for singletons and 2.6 to 8.0 kg for twins. Mean gestation length of 153.4 +/- 0.5 d (range 151 to 160) was slightly longer than the expected norm of about 150 d. The pregnancy rate was significantly higher after the transfer of embryo pairs (64%) than single (39%) embryos, while survival of lambs to weaning was greater for singleton (80%) than for twin lambs (43%). Some factor(s) in the culture media, such as growth factors in the sera, may have a mitogenic effect on embryonic cells, or it may alter the distribution of cells to the trophectoderm and inner cell mass, resulting in enhanced body growth rates.
本文描述了一种用于生产绵羊胚胎的体外培养系统，其中热灭活的绵羊血清被用作成熟、受精和7天培养阶段的蛋白质来源。从商业屠宰场获得的卵巢被用作成熟母羊（285只）和羔羊卵母细胞（356个）的来源，随后将这些卵母细胞在该系统中培养，分别产生相似的平均卵裂率，分别为91%和92%，但囊胚/卵裂卵母细胞的比例显著不同（P<0.025）（分别为46%和18%）。在培养的第7天或第8天，将来自每个来源的胚胎，要么单个（母羊来源），要么成对（母羊和羔羊来源），移植到激素同步的受体母羊中，导致单胎出生的羔羊体重在2.5至8.8千克之间，双胎出生的羔羊体重在2.6至8.0千克之间。平均妊娠期为153.4±0.5天（范围为151至160天），略长于约150天的预期标准。胚胎对移植后的妊娠率（64%）显著高于单个胚胎移植（39%），而单胎羔羊（80%）到断奶时的存活率高于双胎羔羊（43%）。培养基中的某些因素，如血清中的生长因子，可能对胚胎细胞有促有丝分裂作用，或者可能改变细胞向滋养外胚层和内细胞团的分布，从而导致身体生长速度加快。
