Insecticidal activity of temephos against Ctenocephalides felis on dogs and cats

Dogs and cats were treated with 2% temephos [0,0'-(thiodi-p-phenylene) 0,0',0'-tetramethyl bis (phosphorothioate)] powder to evaluate its insecticidal activity against the cat flea (Ctenocephalides felis). Dogs and cats were infested each week with approximately 100 unfed, unsexed fleas less than 14 days old. Live-flea counts were made each day. The experiment was terminated when all dogs and cats retained live fleas for 6 days or more. The 2% temephos powder resulted in excellent flea control on dogs and cats for 2 weeks, partial control for 3 to 4 weeks, and no effective control beyond 4 weeks.