Guinea Pig-Amblyomma Americanum Animal Systemic Insecticide Test, 1978

The procedure is as follows: Guinea pigs are “close-clipped” around the midsection. Then 2 capsule cages are attached with contact cement and tape. Then 24 starved nymphal lone star ticks are placed in the cages (12/capsule), and the candidate compound is administered 24 hr later. Doses are established by weighing the guinea pigs to determine the amount of active ingredient to be used; they depend on structure, LD50, and other compound characteristics though the maximum is 50 mg/kg. This amount is formulated in diethyl succinate and administered subcutaneously in a volume of < 500 μl/injection. The injections are given on 3 alternate or consecutive days. About 4-6 days after the 1st treatment, dead ticks are detached and counted, and/or replete ticks were removed from the capsules and held to observe mortality and nymphal molt.