Efficacy of fipronil in the treatment of pediculosis in laboratory rats

Abstract

As parasitized rodents are not desirable experimental objects, it is important to maintain parasite-free laboratory rodent colonies. Faced with the task of eliminating pediculosis from a conventional laboratory rat colony whose individuals were intended to be used in scientific research, a drug treatment was needed which did not, or minimally, interfere with experimental results. Fipronil, a GABAA antagonist, is an effective drug against lice, fleas and mites currently used in domestic species. Fipronil is not absorbed, has a wide safety margin and is topically applied. The aim of this study was to treat an infected colony with Frontline® Spray (0.25% – w/v – fipronil) in order to evaluate its efficacy against lice. Rats were sprayed with Frontline® only once. Special procedures to prevent cross-contamination between cages were not used. Neither lice nor nits were found during any post-treatment examination. In addition, no complications were reported by any researcher after using the treated rats in their experiments. The results of this study demonstrate that fipronil in topical formulations is effective for treatment and control of sucking and biting lice infestations on laboratory rats.