Haas H J, Spratt N T
Anat Rec. 1976 Feb;184(2):227-31. doi: 10.1002/ar.1091840208.
Explanted blastoderms of freshly laid chicken eggs expand their area during the first 44-45 hours of incubation by a factor of at least 11 if they are placed with the epiblast on the inner surface of explanted fresh chick vitelline membrane and provided with chick egg extract. This expansion is due essentially to the spreading of the yolk sac-serosal membrane. On turkey and duck membrane the expansion factor is about 6 and 3.8 respectively under otherwise identical conditions, but 1.9 only on a semisolid nutrient agar plate. Only the inner surface of the vitelline membrane has this growth-promoting potential, which markedly and progressively declines during incubation in ovo because of systemic factors rather than because of a direct influence by the outgrowing yolk sac-serosal membrane. Trypsinization of fresh chick vitelline membrane (1% trypsin 3 hours) reduces the growth-promoting potential to about 40% of its normal strength. The outgrowth of the extraembryonic tissues on vitelline membrane is better supported in the presence of a species' own egg extract than by extract from another species.
刚产下的鸡蛋的外植胚盘，如果将其胚盘置于新鲜的外植鸡卵黄膜内表面并添加鸡卵提取物，在孵化的最初44 - 45小时内其面积至少会扩大11倍。这种扩大主要是由于卵黄囊 - 浆膜的伸展。在火鸡和鸭的膜上，在其他条件相同的情况下，扩大因子分别约为6和3.8，但在半固体营养琼脂平板上仅为1.9。只有卵黄膜的内表面具有这种促进生长的潜力，由于系统性因素，而非由于生长中的卵黄囊 - 浆膜的直接影响，这种潜力在体内孵化过程中会显著且逐渐下降。新鲜鸡卵黄膜用胰蛋白酶处理（1%胰蛋白酶处理3小时）会使促进生长的潜力降低至正常强度的约40%。与来自其他物种的提取物相比，在自身物种的卵提取物存在的情况下，卵黄膜上胚外组织的生长得到更好的支持。
