Albendazole is effective for controlling monogenean parasites of the gills of Piaractus brachypomus (Serassalmidae) and Leporinus macrocephalus (Anostomidae)

Abstract Aquaculture is the fastest-growing food production industry both in Brazil and globally. Such growth has led to an increase in parasitic diseases such as those caused by monogeneans in farmed fish. Monogenean infection can cause high mortality among commercially farmed fish and therefore significant financial losses. The present study investigated the efficacy of albendazole in therapeutic baths against monogeneans of Piaractus brachypomus and Leporinus macrocephalus. For both fish, a 24h hourtherapeutic bath with albendazole concentrations of 150, 300 and 500 mg/L was tested against monogeneans in the gills. The baths had an efficacy ranging from 30.7 to 96.1% against monogeneans of P. brachypomus, and from 89.2 to 100% against monogeneans of L. macrocephalus. In P. brachypomus, the hepatosomatic index (HSI) in fish exposed to 150 mg/L of albendazole was higher than in fish exposed to 300 mg/L. The splenosomatic index (SSI) values in fish exposed to 150 mg/L of albendazole were lower than in fish exposed to 0 and 300 mg/L. In L. macrocephalus, the HSI and SSI values decreased in treatments with 150, 300 and 500 mg/L of albendazole. For L. macrocephalus, 150 mg/L de albendazole may be used to control and treat of infection by monogeneans, while in P. brachypomus, 500 mg/L of albendazole may be used in a 24 h bath.