Efficacy of Broadline against Capillaria aerophila lungworm infection in cats.

Capillaria aerophila is a globally distributed parasite of the respiratory system of carnivores and can be considered the second most common lungworm after Aelurostrongylus abstrusus in domestic cats in the northern hemisphere. To evaluate the efficacy of Broadline (Merial), a combination of fipronil 8.3% w/v, (S)-methoprene 10% w/v, eprinomectin 0.4% w/v and praziquantel 8.3% w/v against C. aerophila, a controlled study with 20 naturally infected cats was conducted. Following blocking by body weight, cats were allocated randomly to two groups of ten animals each: control (untreated) or treated once with Broadline according to the label instructions. For evaluation of efficacy, faeces were examined for capillarid egg shedding prior to and weekly for 3 weeks after treatment, when the cats were necropsied for C. aerophila recovery. Following single topical administration of Broadline, faecal capillarid egg counts were significantly reduced by 93.5 to 99.1% (p < 0.01) compared to the controls. Cats treated harboured significantly fewer C. aerophila lungworms compared to the untreated controls (efficacy 82.4%, p = 0.016). Results of this study demonstrate that Capillaria lungworm burdens can be markedly reduced and that faecal egg shedding can be substantially lowered or eliminated following a single treatment with Broadline.