Ammonium sulphate induced stress related alterations in the opercular epidermis of the live fish Heteropneustes (Saccobranchus) fossilis (Bloch)

Abstract

Histopathological analysis of the sublethal toxicity induced by 0.2 g/l (10% of 96 h LC50 value) of the inorganic fertilizer ammonium sulphate to the outer and inner opercular epidermis of Heteropneustes fossilis has been made. Density and dimension of the goblet mucous cells (MCs) of the outer opercular epidermis increase enormously in the initial stages of exposure. Perinuclear vacuoles appear in the necrotic epithelial cells (ECs) which also bear pyknotic nuclei before their shedding at several stages of treatment. The club cells also exhibit great vacuolization. The damage becomes more extensive in later stages of exposure when severe wear and tear of the epidermis take place. The inner opercular lining however does not show such massive necrotic changes. Hyperplasia of the ECs and great vacuolization at various stages of exposure are the main histopathological alterations.