EFFECTS OF ICLOSAMIDE AND EUCALYPTUS-CAMALDULENSIS ON BIOMPHALARIA-GLABRATA, THE SNAIL INTERMEDIATE HOST OF SCHISTOSOMA-MANSONI

Toxicity studies were carried out on the snail Biomphalaria glabrata u sing niclosamide (bayluscide) and the extract from dried leaves of Euc alyptus camaldulensis. The snails were exposed to Niclosamide and to a queous and methanolic extracts of E. camaldulensis for 24 h and recove red for 48 h. In niclosamide, the LC50 and LC90 values were 0.063 and 0.126 mg/l, respectively. In aqueous extract, the LC50 and LC90 values were 3049.65 and 5568.33 mg/l; while in methanolic extract, they were 71.59 and 96.73 mg/l. Histological changes were observed in the intes tines, digestive glands and ovotestes of the molluscicides treated sna ils. In the intestines, gaps were formed between the epithelial cells and the connective tissue resulting in the derangement of the ciliated cells. In the digestive glands, the digestive cells became irregular in shape; and both digestive and calcium cells showed considerable shr inkage. The ovotestes of the molluscicides treated snails showed reduc tion in numbers of spermatozoa and oocytes.