Wilmut I, Ritchie W A, Haley C S, Ashworth C J, Aitken R P
AFRC Institute of Animal Physiology and Genetics Research, Edinburgh Research Station, Roslin, Midlothian, UK.
J Reprod Fertil. 1992 May;95(1):45-56. doi: 10.1530/jrf.0.0950045.
A comparison was made of the rate and uniformity of development of embryos recovered from Meishan and European white sows. The time of ovulation was estimated to be 34.3 and 49.0 h after the onset of oestrus in large white and Meishan sows, respectively. Embryos were recovered from a total of 38 Meishan and 37 European pigs between 18 and 219 h after the estimated time of ovulation. Embryos recovered after 18-59 or 44-82 h were classified into one of 11 stages (from early fertilization to early blastocyst), and the maximum blastocyst diameter was measured for embryos recovered 140-219 h after ovulation. There was no evidence of a difference between the genotypes in the stage or size of embryos at these times or of large differences between the genotypes in the extent of variation in embryo stage within females, although a minority of European white females had very variable embryos. As the differences between the embryos of the Meishan and the European white were small, it seems unlikely that greater uniformity of Meishan embryo development is a major cause of the higher prenatal survival in that breed.
对从梅山母猪和欧洲白母猪体内回收的胚胎的发育速度和发育一致性进行了比较。据估计，大白母猪和梅山母猪发情开始后排卵时间分别为34.3小时和49.0小时。在估计排卵时间后的18至219小时内，从总共38头梅山猪和37头欧洲猪中回收胚胎。将在18 - 59小时或44 - 82小时后回收的胚胎分为11个阶段之一（从早期受精到早期囊胚），并测量排卵后140 - 219小时回收的胚胎的最大囊胚直径。在这些时间点，没有证据表明不同基因型在胚胎阶段或大小上存在差异，也没有证据表明雌性体内胚胎阶段的变异程度在不同基因型之间存在很大差异，尽管少数欧洲白猪雌性的胚胎非常多变。由于梅山猪和欧洲白猪胚胎之间的差异很小，梅山猪胚胎发育更高的一致性似乎不太可能是该品种产前存活率较高的主要原因。
