Impact of the insecticide endosulfan on growth of the African giant snail Achatina achatina (L.)

Abstract

The impact of the insecticide endosulfan was assessed on the growth of the African giant snails, litterliving animals found in cocoa fields throughout tropical Africa. Two doses of endosulfan, C1, 6.25 a.i g/l and C2, 12.50 a.i g/l were applied twice with one month of interval to the litter of the snails. After quarantine, snails were allowed to feed on this litter and the elongation of their shells as well as their growth was measured every nine days. The results, daily weight gain (g/j) of -0.028 ± 0.004 for C1 and - 0.033 ± 0.007 for C2 showed that snails which received endosulfan in their feed had a very weak growth compared to the control one, which have a daily weight gain of 0.032 ± 0.006. The product seems to disrupt weight regulation. But the insecticide had little influence on the shell elongation. High dose o endosulfan reduced more the weight gain and shell elongation compared to the recommended dose for insects control in cocoa plantation. These results implied that the repeated application of endosulfan for pest control in cocoa plantations may impair the growth of African giant snails.

Key words: Achatina, endosulfan, pest control, insecticide, cocoa.