Ecology of the parasitic endohelminth community of Pseudoplatystoma fasciatum (Linnaeus, 1776) (Siluriformes: Pimelodidae) from the Aquidauana River, Pantanal, State of Mato Grosso do Sul, Brazil

Abstract

This study investigated the structure and diversity of the endohelminth community and its interactions with Pseudoplatystoma fasciatum, caught in the Aquidauana River, in the State of Mato Grosso do Sul, Brazil. Ten helminth species were represented in 1,228 specimens of parasites found in the intestine and mesentery of 33 specimens of P. fasciatum. Cestodes were observed in the intestine, while nematodes Cucullanus sp. in the mesentery. Contracaecum sp. Type 1, Spatulifer rugosa and Choanoscolex abscisus showed the highest mean intensity and mean abundance and Nomimoscolex sudobin showed the highest prevalence. Simpson's index indicated dominance in the endohelminth infracommunities (C = 1.0792) and Choanoscolex abscisus was considered the central species. A clumped pattern of dispersion according to Green's index was related. 69.69% of hosts analyzed had between 2 and 5 species of endohelminths. Mean diversity was H = 0.5517 (SD = 0.4209). Two pairs of species showed significant positive association and four pairs presented significant positive correlation among abundance data. Significant negative correlations between total length and prevalence and abundance of Peltydocotyle rugosa and Nomimoscolex sudobim were found. However, no significant correlation was observed between condition factor and abundance, as well as total length and diversity. There was significant prevalence of Harriscolex kaparari in male hosts. Keywords

Temporal and spatial variations in the metazoan parasite communities of the Panama spadefish, Parapsettus panamensis (Pisces: Ephippidae), from the Pacific coast of Mexico

“…Those patterns suggest that stronger infracommunity structure among smaller fish is not caused by a difference in period of parasite accumulation and exposure to infection, as has been suggested for other host species. Higher prevalence or abundance of some parasites in small fish can be the result of several other factors: young fish may acquire parasites that are later eliminated once the fish are adults (e.g., by the development of an immune reaction in older organisms); young fish may differ from older fish in preying on some forage species that act as intermediate hosts (Campos, Fonseca, Takemoto, & Moraes, ; Luque & Chaves, ); or the degree to which fish aggregate in shoals (and risk of infection by association with other infected individuals) may be reduced as fish get larger (Hemelrijk & Kunz, ). Some of these factors could also explain the greater abundance of copepods in individuals of P. panamensis of smaller body size.…”

Parasitological assessment in the hybrid surubim (Pseudoplatystoma reticulatum x P. corruscans), with uncommon occurrence of Monogenea parasites

“…(SANTOS et al, 2003;CAMPOS et al, 2009), no reports were until now observed in the hybrid surubim. Its occurrence in farmed hybrid surubim was lower than that observed in cachara (P. reticulatum) from the natural environment (CAMPOS et al, 2008).…”

Harriscolex nathaliaeN. Sp. (Cestoda: Proteocephalidea) fromPseudoplatystoma corruscans(Siluriformes: Pimelodidae) in the Paraná River Basin, Argentina

“…Recently, an ecological survey of the parasitic endohelminth community of Pseudoplatystoma fasciatum (Linnaeus) in Mato Grosso do Sul State (Brazil) recorded H. kaparari (Campos et al, 2009). Unfortunately, this species was not measured and there is no information on deposition of voucher specimens at any collection for future morphological studies.…”