Interference with Fasciola hepatica snail finding by various aquatic organisms

Area of Science:

• Parasitology
• Ecology
• Aquatic Biology

Background:

• Fasciola hepatica miracidia infect intermediate host snails, Lymnaea truncatula.
• Previous studies indicate non-host organisms can interfere with miracidial infection.
• Understanding interference mechanisms is crucial for parasite control strategies.

Purpose of the Study:

• To investigate the potential of various aquatic organisms and environmental factors to interfere with Fasciola hepatica miracidial infection of Lymnaea truncatula.
• To determine if predatory behavior contributes to interference effects.

Main Methods:

• Experimental setup using linear test channels with target snails (Lymnaea truncatula).
• Introduction of potential interferents: Daphnia pulex, Corethra sp. larvae, various aquatic invertebrates (leeches, isopods, flatworms), Lymnaea truncatula egg clusters, and conditioned water.
• Assessment of miracidial infection rates in target snails with and without interferents.

Main Results:

• Daphnia pulex and Corethra sp. larvae significantly reduced miracidial infection rates of Lymnaea truncatula.
• Evidence suggests the interference by Daphnia pulex and Corethra sp. larvae is due to their predatory activity.
• Herpobdella testacea, Helobdella stagnalis, Acellus aquaticus, Planaria lugubris, L. truncatula egg clusters, and conditioned water did not interfere with miracidial host-finding or infection.

Conclusions:

• Certain zooplankton species, through predation, can act as biological control agents against Fasciola hepatica miracidia.
• The findings highlight the ecological interactions that can influence parasite transmission dynamics.
• Further research into predator-prey interactions could offer novel approaches for managing fasciolosis.