Communities of parasite metazoans in Piaractus brachypomus (Pisces, Serrasalmidae) in the lower Amazon River (Brazil)

Abstract

The aim of this study was to investigate the component community of parasite metazoans of Piaractus brachypomus in the lower Amazon River, northern Brazil. From 34 necropsied fish, 27,384 metazoan parasites were collected, such as Anacanthorus spathulatus, Mymarothecium viatorum and Notozothecium janauachensis (Monogenoidea); Spectatus spectatus and Contracaecum sp (Nematoda); Clinostomum marginatum and Dadaytrema oxycephala (Digenea); and Argulus carteri and Ergasilus sp. (Crustacea). The dominant species was S. spectatus followed by monogenoidean species, and there was aggregated dispersion of parasites, except for D. oxycephala and Contracaecum sp., which presented random dispersion. Positive correlation among the abundance of the three monogenoideans species were found, thus indicating that there was no competition between the species of these parasites on the gills of hosts. The abundances of some parasite species showed positive correlations with the size of the hosts, but the condition factor of the fish was not affected by the parasitism levels. It showed that this host had a metazoan community characterized by high species richness of metazoans, low evenness and high diversity of parasites, with prevalence of endoparasites, including larval stages. This was the first record of C. marginatum, A. carteri, Ergasilus sp. and Contracaecum sp. for P. brachypomus.Keywords: Amazon, diversity, endoparasites, helminths, freshwater fish. ResumoO objetivo deste estudo foi investigar a comunidade componente de parasitos metazoários em Piaractus brachypomus no baixo Rio Amazonas, Norte do Brasil. Em 34 peixes necropsiados, 27.384 parasitos foram colhidos, tais como Anacanthorus spathulatus, Mymarothecium viatorum, Notozothecium janauachensis (Monogenoidea), Spectatus spectatus, larvas de Contracaecum sp. (Nematoda), Clinostomum marginatum, Dadaytrema oxycephala (Digenea), Argulus carteri e Ergasilus sp. (Crustacea). A dominância foi de S. spectatus, seguida por espécies de monogenoideas, e houve dispersão agregada dos parasitos, exceto D. oxycephala e Contracaecum sp., que apresentaram uma dispersão randômica. Foi encontrada correlação positiva entre a abundância das três espécies de monogenoideas, indicando que não houve uma competição entre as espécies desses parasitos nas brânquias. A abundância de algumas espécies de parasitos mostrou correlação positiva com o tamanho dos hospedeiros, e o fator de condição não foi afetado pelos níveis de parasitismo dos peixes. Mostrou-se que esse hospedeiro teve comunidade de metazoários, caracterizada por elevada riqueza de espécies, baixa uniformidade e elevada diversidade de parasitos com predominância de endoparasitos, inclusive em estágios larvais. Esse é o primeiro relato de C. marginatum, A. carteri, Ergasilus sp., e Contracaecum sp. para P. brachypomus Palavras-chave: Amazônia, diversidade, endoparasitos, helmintos, peixe de água doce.

Community ecology of parasites in four species of Corydoras (Callichthyidae), ornamental fish endemic to the eastern Amazon (Brazil)

“…A fundamental aspect of the host-parasite interaction is related to the distribution pattern of parasites among hosts. The distribution of parasites in freshwater fish is typically aggregated (Guidelli et al 2003, Poulin 2013, Amarante et al 2015, Oliveira and Tavares-Dias 2016. The aggregated dispersion of parasites has been attributed to the heterogeneity of the environment and to susceptibility of the host population to the parasites (Poulin 2013).…”

“…Thus, aggregated dispersion pattern of parasites in C. ephippifer, C. melanistius and C. spilurus was found, as expected. In contrast, the dispersion of P. (S.) inopinatus in C. ephippifer was random, a distribution pattern that occurs mainly in parasite species with moderate or high pathogenicity and with low ability for colonizing hosts in environments (guidelli et al 2003, Oliveira andTavares-Dias 2016).…”

“…However, the pentastomid of C. spilurus seem be of the genus Sebekia. Abiotic and biotic factors have been also associated with the diversity and abundance of helminths in wild fish populations (Bautista-Hernández et al 2014, Salgado-Maldonado et al 2016, Oliveira and Tavares-Dias 2016.…”

“…Nevertheless, correlation between parasites abundance with host body size is far from universal. The host size can either be related or not to its age, once the parasitic population may increase, decrease or not suffer effect from its size and age (guidelli et al 2003, Rolbiecki 2006, Oliveira and Tavares-Dias 2016.…”

Multiparasitism in gills of Metynnis lippincottianus from the environmental protection area of Curiaú river, Eastern Amazon

“…Multiple studies have reported that gills are one of the most parasitized organs (CARDOSO et al, 2018;JERÔNIMO et al, 2014, GONÇALVES et al, 2014, VENTURA et al, 2013, SANTOS et al 2013OLIVEIRA et al, 2016). Gills are easily damaged by parasitic infections, being the first organ in contact with the external environment.…”