Combination of molluscicides with attractant carbohydrates and amino acids in bait formulation against the snail Lymnaea acuminata.

Aim: Fascioliasis is an impor- tant helminth disease caused by Fasciola (F.) he- patica and F. gigantica of Asia and Africa. This disease belongs to the plant-borne trematode zoonoses. Human infection has been reported in 51 different countries from 5 continents. One of the possible approaches to control this problem is to interrupt the life cycle of the parasitic trematodes by eliminating the snail. Materials and Methods: Snails attractant pellets (SAP) were prepared from binary combi- nation of carbohydrate + amino acid (20 mM) in 2% agar solution with active molluscicidal com- ponent Ferula asafoetida (ferulic acid, umbellif- erone), Syzygium aromaticum (eugenol), Carum carvi (limonene). Attraction of snails to different combinations was studied by using clear glass aquaria having diameter of 30 cm. Each aquari- um was divided into four concentric zones; zone-3 (central zone), zone-2 and zone-1 (mid- dle zone) and zone-0 (outer zone) had a diame- ter of 13, 18, 24, and 30 cm, respectively. The behavioral responses of snails to these binary combinations of carbohydrate and amino acid in bait formulation were examined. The fraction of snails that was in contact with the SAP at different times was used as a measure of at- traction. Results: Among all the binary combination of carbohydrate+amino acid+molluscicide after 2h of experiment, highest attraction of snail (54.71%) was observed towards the SAP con- taining starch+histidine+limolene. Limonene+ starch+histidine containing SAP emerged as the strongest bait formulation (96h LC50 0.74%) against Lymnaea acuminata. Conclusions: The present study suggested that the molluscicides of plant origin could be used with varying degrees of success in bait for- mulation.