Laboratory Evaluation of the Molluscicidal Activity of Calcium Hypochlorite on Intermediate Hosts of Paragonimiasis

A laboratory investigation was conducted to assess the molluscicidal effect of calcium hypochlorite on two species of Potadoma snails: Potadoma moerchi and Potadoma freethi. 90 snails per species were collected from a stream in Ipogun village, Ondo State, Nigeria. Five (5) concentrations of calcium hypochlorite (45mg/l, 65mg/l, 85mg/l, 105mg/l, and 125mg/l) were prepared for the experiment using well water. The snails were then exposed to the different concentrations of the calcium hypochlorite solution in glassware for 48 hours with 3 replicates per treatment in a completely randomized design to determine the LC50 and LC90. A control treatment was also set up for the experiment using well water. The results showed that Calcium hypochlorite had a remarkable molluscicidal activity on the snails, with a 93.33% percentage mortality rate recorded in Potadoma moerchi at 48 hours and 100% recorded from 32 hours for Potadoma freethi snails in the two highest concentrations. After the 48-hour assay, the mean LC50 and LC90 for P. moerchi were 91.42mg/l and 126.27mg/l, while the mean LC50 and LC90 for P. freethi were 51.98mg/l and 94.33mg/l. Calcium hypochlorite demonstrated effective molluscicidal activity against both snails and may be useful in controlling intermediate hosts of paragonimiasis, and its deployment in slow-flowing or stagnant water bodies