EFFICACY OF FENTHION AGAINST THE FLEA, CTENOCEPHALIDES-FELIS, ON THE CAT

A controlled study was carried out in two replicated trials, each usin g three groups of domestic cats artificially infested with Ctenocephal ides felis. In each trial three cats were treated with fenthion, three were treated with a dichlorvos/fenitrothion formulation, both at the recommended dose rate and the remainder acted as untreated controls. G ood knockdown efficacy was evident 24 hours after both treatments. Eff icacy values of 85 per cent or more were maintained for at least 15 da ys with fenthion and for less than eight days with dichlorvos/fenitrot hion.