Histometrical and histochemical studies of alarm mucous cells in different regions of mature male and female epidermis of Silver carp (Hypophthalmichthys molitrix)

Abstract

Fish epidermis contains alarm mucous cells which they react to environmental stressful factors, diseases and damages to skin. For histometrical and histocheical studies of these cells, at least 10 mature male and female silver carp were selected and 5 mm thickness samples were taken from different parts of skin including head, dorsal, ventral and tail. 5-6μ sections were made using paraffin embedding methods, and stained by general staining of H&E histochemical staining including; PAS and alcian blue (AB) with PH 1 and 2.5. Numbers of alarm cells were counted in 100μ length of epidermis in each region. The results showed that there are voluminous and ellipsoid cells called alarm mucous cells in different regions of silver carp epidermis. These cells have positive reaction to AB staining in PH 1 and 2.5 which it showing the acidic and sulfated property of mucous secretion of these cells. The skin of silver carp fish can divided basis to alarm cells distribution in different parts of epidermis (head , dorsal regions, ventral regions and tail); in mature male fish: The maximum and minimum number of alarm cells in 100μ length of epidermis are in ventral (5.40±1.26) and tail (0.92±0.19) skin respectively but in mature female fish: The maximum and minimum were seen in head (6.06±1.99) and tail (0.97±0.44) skin respectively.