Biochemical and Histological Alterations in the Digestive Gland of the Land Snail Helicella vestalis (Locard, 1882) Exposed to Methiocarb and Chlorpyrifos in the Laboratory

This study investigated the impact of two pesticides namely Methiocarb and Chlorpyrifos against the biochemical and histological aspects of the helicid land snail, Helicella vestalis at Sharkia Governorate, Egypt. The activities of three vital enzymes, total protein (TP) and total lipid (TL) were laboratory tested. These enzymes were Aspartate amino transaminase (AST), Alanine amino transaminase (ALT) and Alkaline phosphatase (ALP). Results showed that all tested pesticides lead to increase the activity of AST, ALT and ALP in the tissue homogenate of the digestive gland of the land snail Helicella vestalis. On the other hand, the levels of total protein and total lipid were increased after treatment with all tested pesticides. In general, the two pesticides were significantly affected on the activities of enzymes, total lipid and total protein compared with control when applied against the tested snails. Meanwhile, many histological changes were observed in the digestive gland of H. vestalis after exposure to sublethal concentrations of both Methiocarb and Chlorpyrifos. These alterations included severe tubular disruption, vaculation, nuclear pyknosis and necrosis of tubules. Moreover, this study revealed that Chlorpyrifos was much more toxic to the tested snail than Methiocarb.