Histomorphological and Ultrastructural Studies on the Paraepiglottic Tonsil in Goats during Postnatal Period

Abstract

Histology, ultrastructure and post-natal development of paraepiglottic tonsil were studied in 36 apparently healthy male goats from one month to six months of age. The paraepiglottic tonsil was seen in all the goats studied and was a small elevation located lateral to the epiglottis in the ventromedial aspect of the pharyngeal side wall. It was lined by non-keratinised stratified squamous surface epithelium which was modified into reticular epithelium with fewer cell layers and excessive infiltration of lymphoid tissue at areas above lymphoid nodules. Distinct crypts were not seen. The lamina propria was composed of diffuse and nodular aggregations of lymphoid cells present as tonsillar nodules. The scanning electron microscopy of paraepiglottic tonsils of postnatal age groups showed flat, angular squamous cells in the surface epithelium covered by densely packed microplicae and smaller round to oval cells covered by closely packed knob-like, microvilli. The reticular epithelium was disrupted at places and lymphoid cells were seen projecting through it. In cut sections of the palatine tonsils, the lymphoid nodules were seen with large number of small, medium and large lymphocytes.