A NOVEL-APPROACH TO FLEA CONTROL ON CATS, USING PYRIPROXYFEN

Pyriproxyfen is a new insect growth regulator,vith potent activity aga inst developing stages of the cat flea, Ctenocephalides felis. To dete rmine its duration of action after application as a spot-on topical tr eatment, 20 cats were allocated to two groups, One group acted as untr eated controls, and each cat in the other was given a single dose of 1 mg/kg pyriproxyfen. Each cat was infected with fleas at weekly interv als and caged. Eggs were collected and their viability determined as a measure of the effect of the agent on adult fleas. The effect of the transfer of pyriproxyfen from each; cat to its immediate surroundings was monitored by observing the development of fertile flea eggs placed on samples of blanket taken from each cage, Results from untreated co ntrol cats showed that the experimental conditions were favourable for the lifecycle of the nea. Flea reproduction on treated cats was inhib ited completely for seven weeks and substantially for at least a furth er two weeks, Blankets used by cats treated up to two weeks previously prevented flea development entirely and substantial control was still achieved up to four weeks after treatment.