| Abstrakt: |
Structural abnormalities of the head and throat of ear-tufted embryos of the Araucana fowl are described. These abnormalities involved the opening to the external auditory meatus and such bones as the mandible, quadrate, columella auris, squamosal, and hyoid apparatus. Structural irregularities are believed to be due to the presence of the Et gene and its influence on the early embryonic closure of the hyomandibular cleft. The diversity of phenotypic expression probably is due to the varied closure of the cleft. |
