Squamous metaplasia of oesophageal mucous glands in a non-descript duck

Squamous metaplasia is the replacement of normal cuboidal or columnar epithelium by stratified squamous epithelium. The squamous metaplasia of oesophageal mucous glands in a non-descript female duck has been described here. The necropsy findings revealed pale kidneys with marked tubular distension. The oesophageal mucosa showed numerous prominent whitish nodules of about 1mm size diameter approximately. The histopathological examination of kidney showed empty spaces surrounded by fibrous connective tissue and severe infiltration of inflammatory cells namely macrophages, lymphocytes and plasma cells. The section of oesophagus showed cystic, dialated and keratin filled mucosal glands. Squamous metaplasia was evident in the esophageal mucosal glands. This could be a visible indicator of vitamin A deficiency. Vitamin A deficiency may occur in birds which are feed exclusively on grains as grains contain only trace amounts of vitamin A.