The efficacy of imidacloprid against flea infestation on dogs compared with three other topical preparations

New effective, long-lasting and easy-to-apply insecticides for control of f leas in pets are required in veterinary practice to overcome the increasing flea problems worldwide. Imidacloprid is a new active ingredient with high activity against fleas. The objective of this study was to compare the eff icacy of the recommended dosage and application of tree commercial products wit the new compound imidacloprid against fleas in dogs The study was cond ucted in accordance with the code of Clinical Trials on Veterinary Medical Products of the EU. Dogs (25 Beagles) were allocated to equal groups of fiv e animals in which each animal was experimentally infested with 100 adult C tenocepalides felis twice before and six times posttreatment at weekly inte rvals. dogs in four groups were treated with imidacloprid, fipronil, permet hrin and diazinon. A fifth group of dogs remained as untreated control. Fle as were counted at 24, 48, and 72 hours after reinfestation on dogs by usin g a comb. An immediate (24 hours) 100% killing effect was seen in all treat ed animals. In dogs, 100% efficacy was observed in all treatment groups unt il the evaluation after the third reinfestation. After the reinfestation th ree weeks post treatment (pt), only those dogs treated with imidacloprid an d with diazinon were still free of fleas. On day 37 pt, the reduction was 5 5% with permethrin, 83% with fipronil, 86% with diazinon, and 99.8% with yo udacloprid. The trial results demonstrate the high efficacy of imidacloprid against fleas in dogs when compared to other commercial products. The exce llent knock-down effect and the long lasting 100% control of fleas, togethe r with the advantages of safety and simple application make the product a u seful tool for flea control.