EFFICACY OF LUFENURON AGAINST DEVELOPMENTAL STAGES OF FLEAS (CTENOCEPHALIDES-FELIS FELIS) IN DOGS HOUSED IN SIMULATED HOME ENVIRONMENTS

Twenty-four, adult, female Beagles were arranged by body weight from g reatest to least and allocated to 2 groups of 12 dogs, using random nu mbers. Dogs were housed collectively in 2 adjacent metal buildings, ea ch divided into 4 rooms measuring 2.1 x 3.7 m. Each room was paneled a nd carpeted and had an access door to the outside with a connecting ru n that measured 2.1 x 9.1 m. Each run had a surface consisting of 5 cm of pea gravel overlaying 5 cm of sand, and was partially covered by a n awning that provided shade at its proximal end. For placement in roo m/run units, dogs in each of the treated and control groups were allot ted to 4 subgroups of 3 dogs each. Each subgroup of dogs was placed in a separate room/run unit. Units containing treatment or control subgr oups were alternated to avoid placing identically treated subgroups ad jacent to each other. Dogs of subgroups A, C, E, and G were treated wi th lufenuron monthly at a minimal target dosage of 10 mg/kg of body we ight; those of subgroups B, D, F, and H were treated with excipient ta blets. Dogs were treated on study days 7, 37, 68, and 98. Each dog was infested with 100 newly emerged, unfed, insectary-reared, adult Cteno cephalides felis on each of study days 0 and 2. Thereafter, infestatio ns on all dogs were dependent on continued development of fleas either in the indoor or outdoor environment. Numbers of fleas on each of the treated and control dogs were determined, using a nondestructive coun ting technique on days 6, 14, 21, 28, 35, 56, 70, 84, 98, 112, and 119 . On study day 21 and on each collection day thereafter, numbers of ad ult fleas recovered from treated dogs were significantly (P less than or equal to 0.05) fewer than those recovered from control dogs. Propor tion reduction of fleas on treated vs control dogs exceeded 90% by stu dy day 35 and 95% by study day 56. Efficacies exceeded 95% on all rema ining study days except days 98 (94.4%) and 119 (90%). Results of this study indicate that control of flea populations can be achieved in tr eated dogs approximately 4 to 5 weeks after initial treatment with luf enuron, and that continued monthly treatments will maintain effective control of flea infestations. Adverse reactions or side effects to tre atment with lufenuron were not observed in dogs after treatment at any time throughout the study.