The dynamics of trematode infected and uninfected Planorbella trivolvis in commercial catfish ponds

Planorbella trivolvis, a snail routinely found in catfish ponds, is an intermediate host in the life cycle of Bolbophorus damnificus, a digenetic trematode responsible for mortalities in catfish. This research generated information on the life cycle and the population dynamics of P. trivolvis in catfish ponds which could be implemented to control P. trivolvis. Research indicated that: P trivolvis is present year-round; survives overwintering at water temperatures of 5°C; reproduces year-round; is found in vegetation, sediment and water in ponds year-round; lays eggs two months post-hatch; and has a life span of at least one year. Planorbella trivolvis infected with Bolbophorus spp. were found in 0.8% of the snails examined; found in juvenile snails (4 mm), and could shed 3,200 cercariae/day, and shed these cercariae for up to 21 days. This data indicated that constant snail monitoring and persistent snail control is imperative to control P. trivolvis in catfish ponds