Shah R M, Cheng K M, MacKay R A, Wong A
Department of Oral Biology, Faculty of Dentistry, University of British Columbia, Vancouver, Canada.
J Anat. 1987 Oct;154:245-58.
Prenatal development of the secondary palate in duck was studied using light and electron microscopic, histochemical, autoradiographic and biochemical techniques. The secondary palate of duck develops between Days 7-12 of incubation (HH 25-37). During this period the palatal shelves grow horizontally toward one another but, unlike those in mammals and the alligator, they never fuse, and a physiological cleft persists between them. In contrast to both chick, where the MEE differentiates to orthokeratinisation, and quail, where the MEE becomes parakeratinised, the MEE of duck differentiates to a non-keratinised stratified type. A continuation of DNA synthesis in the MEE, unchanged levels of cyclic AMP in the palatal tissues and an absence of programmed cell death in the MEE during duck palatogenesis distinguish it from the mammalian palate morphogenesis. Also, although the morphogenesis of palate in duck, chick and quail is similar, the cytodifferentiation of their MEE is different.
利用光学显微镜、电子显微镜、组织化学、放射自显影和生化技术研究了鸭次生腭的产前发育。鸭的次生腭在孵化第7至12天（HH 25 - 37）发育。在此期间，腭突向彼此水平生长，但与哺乳动物和短吻鳄不同的是，它们从不融合，两者之间始终存在生理性裂隙。与鸡的MEE分化为正角化、鹌鹑的MEE分化为不全角化不同，鸭的MEE分化为非角化复层类型。鸭腭发育过程中MEE中DNA合成的持续、腭组织中环状AMP水平的不变以及MEE中程序性细胞死亡的缺失使其与哺乳动物腭形态发生区分开来。此外，尽管鸭、鸡和鹌鹑腭的形态发生相似，但其MEE的细胞分化不同。
