Mayerson P L, Fallon J F
J Exp Zool. 1984 Nov;232(2):231-42. doi: 10.1002/jez.1402320210.
The normal timing and appearance of feather germs was perturbed by injecting the dye Janus Green B into the amniotic fluid of chick embryos at late stage 28, prior to the first appearance of feather germs. This treatment prevented feather germ morphogenesis in some regions while elsewhere it delayed normal morphological development. The Janus Green B effect lasted for approximately 98 hours. Feather regions, which normally form epidermal placodes during the period of treatment, showed the longest delays in subsequent feather germ formation and were the most likely to remain featherless. These results suggest that the epidermal placode stage is critical for feather germ formation. Janus Green B appears to prevent feather germ morphogenesis by interfering with development prior to this critical stage. Since severely affected regions fail to recover their capacity to form feather germs, even after the period of sensitivity to the dye, a limited period of competence is suggested for feather germ formation.
在第28期后期，即在羽芽首次出现之前，将染料中性红注入鸡胚羊膜液中，这扰乱了羽芽的正常形成时间和外观。这种处理在某些区域阻止了羽芽形态发生，而在其他地方则延迟了正常的形态发育。中性红的作用持续约98小时。在处理期间正常形成表皮基板的羽区，在随后的羽芽形成中延迟最长，并且最有可能保持无毛。这些结果表明，表皮基板阶段对羽芽形成至关重要。中性红似乎通过在这个关键阶段之前干扰发育来阻止羽芽形态发生。由于严重受影响的区域即使在对染料敏感的时期过后也无法恢复形成羽芽的能力，因此提示羽芽形成存在有限的感受态期。
