Histological Study on Pharynx and Esophagus of Red Panda

The wall of the pharynx consists of tunica mucosa, tela submucosa and pharyngeal muscle. Especially, there are lots of skeletal muscle fibers in the tela submucosa besides the mixed gland. The wall of the esophagus is composed of tunica mucos, tela submucosa,tunica muscularis and fibrose. The individual differences take place in thickness of the wall,diameter of the cavity and existence of the esophageal longitudinal fold. The papillae of the lamina propria stretch into the stratified squamous epithelium.There are plenty of esophageal glands in the tela submucosa. The tunica muscularis which is all skeletal muscle from the front part to the behind part of the esophagus has inner and outer two layers, whose arrangement of the muscular fibers has diversities. The esophageal tissue structure in red pandas has been compared with that in giant pandas.