From Africa to Brazil: detection of African Oreochromis niloticus parasites in Brazilian fish farms

Abstract Aim To evaluate the introduction of Oreochromis niloticus gill parasites in the Paranapanema River basin, northern Paraná, southern Brazil, as well as to inventory its occurrences in Brazilian fish farms and discuss the risks of transmission to native fauna. Methods The gills of 632 fish specimens from four fish farms in the Paranapanema Basin were analyzed. The parasites were collected, processed and identified according to specific procedure. Literature review was carried out to compile records of occurrence of gill parasites species in other Brazilian river basins. Results A total of seven (7) species of parasites were recorded, five (5) of the genus Cichlidogyrus, one (1) of Scutogyrus (Ancyrocephalidae, Monogenoidea) and one (1) of Lamproglena, Lamproglena monodi (Copepoda, Lernaeidae). All native from Africa. Some of these species have been reported in fish farms located in five other Brazilian watersheds. However, in this study a greater number of African gill parasite species was recorded in fish farms in northern Paraná (seven species), in the Paranapanema Basin, with Cichlidogyrus rognoni reported only for this basin. Conclusions The results confirm the introduction of these African parasites along with their host, O. niloticus, and the establishment of these species in Brazilian waters, since many specimens belonging to the species identified herein presented breeding activity for at least one period of the year. Although, only L. monodi has been recorded parasitizing Brazilian native species, data reported for other countries demonstrates the imminent risk of transmission of these O. niloticus parasites to native cichlids. Resumo Objetivo Avaliar a introdução de parasitos branquiais de Oreochromis niloticus na bacia do rio Paranapanema, norte do Paraná, sul do Brasil, assim como inventariar suas ocorrências em pisciculturas brasileiras e discutir os riscos de transmissão para a fauna nativa. Métodos As brânquias de 632 espécimes de peixes de quatro estações de piscicultura na bacia do rio Paranapanema foram analisadas. Os parasitos foram coletados, processados e identificados de acordo com procedimento específico. A revisão da literatura foi realizada para compilar registros de ocorrência de espécies parasitas branquiais em outras bacias hidrográficas brasileiras. Resultados Um total de sete (7) espécies de parasitos foi registrado, sendo cinco (5) do gênero Cichlidogyrus, uma (1) de Scutogyrus (Ancyrocephalidae, Monogenoidea) e uma (1