ABSTRACT This study investigated the parasite fauna in Piaractus brachypomus grown in fish farms in the state of Acre, in the western Brazilian Amazon. We examined 160 fish from four farms. Overall parasite prevalence was 66.9%. The fish were parasitized by Anacanthorus spathulatus, Mymarothecium viatorum, Anacanthorus penilabiatus, Clinostomum marginatum, Echinorhynchus jucundus and Henneguya sp., but monogenean species were the dominant parasites. Monogeneans showed an aggregated distribution pattern and there was a weak correlation between host size and abundance of M. viatorum and A. penilabiatus. No difference in the condition factor of parasitized and non-parasitized fish was detected. The fish of all farms had the gills parasitized by A. spathulatus... |