EVALUATION OF HYPERACTIVITY PRODUCED BY PYRETHROID TREATMENT ON 3RD INSTAR NYMPHS OF TRIATOMA-INFESTANS (HEMIPTERA, REDUVIIDAE)

The hyperactivity produced in third instar nymphs of Triatoma infestan s by their exposure to films of deltamethrin or cis-permethrin was eva luated. Both pyrethroids produced a significant increase in locomotor activity at 26 and 36 degrees C but not at 16 degrees C. At 26 degrees C, only deltamethrin produced hyperactivity when topically applied on the dorsal side of the nymph's abdomen. However, both pyrethroids pro duced hyperactivity when topically applied on the head of the nymphs. Hyperactivity was not observed when nymphs were treated with N-ethylma leimide (20 mu g/insect) before exposure to the pyrethroids. The effec t of both insecticides on locomotor activity reversed the inhibitory i nfluence on locomotion elicited by contact with the walls of the exper imental arena (thigmotaxis). (C) 1997 Wiley-Liss, Inc.