Albendazole and praziquantel efficacy against Anacanthorus penilabiatus (Monogenea: Dactylogyridae), gill parasite of Piaractus mesopotamicus (Osteichthyes: Characidae). I. Therapeutic baths

Abstract

This study evaluated the efficacy of short term bath with albendazole sulfoxide (ABZ) and praziquantel (PRZ) against the monogenean helminth Anacanthorus penilabiatus, gill parasite of pacu Piaractus mesopotamicus. Ninety fish naturally infested were submitted to treatments with 50, 100, 200 and 500 mg of ABZ or PRZ/L of water. Seven days after the exposure, the group treated with 500 mg of PRZ/L presented 68.3% of effectiveness, the highest of this work. The doses of 50 and 500 mg of ABZ/L exhibited effectiveness of 56.9%, and 52.5% to the dose of 200 mg ABZ/L. Fourteen days after the treatments, the dose of 200 mg of PRZ/L demonstrated low efficacy (40.5%). The results of albendazole application at 200 and 500 mg/L produced low effectiveness, 46.5% and 32.75%, respectively. Praziquantel caused toxicity in the fish, and the period of tolerance was 2, 4, 7 and 14 minutes, respectively for 500, 200, 100 and 50 mg PRZ/L. On the other hand, albendazole, even in a period of 30 minutes, did not present poisonous effects, but their antihelmintic effectiveness was low, showing 46.5% and 32.8% efficacy, respectively for 200 and 500 mg ABZ/L. In the used dosages, albendazole and praziquantel are not effective to control Anacanthorus penilabiatus in pacu.