Metazoários parasitos de seis espécies de peixes do Reservatório de Lajes, Estado do Rio de Janeiro, Brasil

Abstract

<jats:p>Entre abril de 2002 e julho de 2003, foram necropsiados 231 espécimes de peixes: 39 Astyanax bimaculatus (Linnaeus, 1758), 79 A. fasciatus (Cuvier, 1819), 23 Hypostomus affinis (Steindachner, 1877), 26 Hoplias malabaricus (Bloch, 1794), 30 Loricariichthys castaneus (Castelnau, 1855) e 34 Trachelyopterus striatulus (Steindachner, 1876) provenientes do Reservatório de Lajes (22º42' - 22º50'S, 43º53' 44º05'O), Estado do Rio de Janeiro, Brasil, para estudo das suas comunidades parasitárias. A maioria dos espécimes de H. affinis (95,6%) e H. malabaricus (84,6%) estavam parasitados por pelo menos uma espécie de metazoário. Em A. bimaculatus, A. fasciatus, L. castaneus e T. striatulus 41%, 39,2%, 56,7% e 14,7% dos espécimes estavam parasitados, respectivamente. Foram coletadas oito diferentes espécies de metazoários parasitos: 2 em A. bimaculatus, 3 em A. fasciatus, 3 em H. affinis, 4 em H. malabaricus, 4 em L. castaneus e 1 em T. striatulus. As comunidades de metazoários parasitos das seis espécies de peixes estudadas apresentaram típico padrão de distribuição agregada. Foram observados dois casos de correlação negativa entre a abundância e a prevalência parasitárias e o comprimento total dos hospedeiros. A comunidade parasitária de L. castaneus apresentou os maiores valores de intensidade média, índice de dispersão e diversidade. As comunidades parasitárias dos peixes estudados apresentaram escassez de correlação entre a abundância, riqueza parasitária e diversidade com o comprimento total dos hospedeiros. Os baixos valores de riqueza e diversidade das comuni-dades parasitárias podem ser atribuídos as características oligotróficas do Reservatório de Lajes.</jats:p>

Metazoan parasite communities of Leporinus macrocephalus (Characiformes: Anostomidae) in cultivation systems in the western Amazon, Brazil

“…The aggregated dispersion of metazoan parasites in L. macrocephalus found in our study is a common pattern in parasite communities of freshwater fish in different regions of Brazil (Machado et al 1996;Abdallah et al 2004;Moreira et al 2005;Paraguassú and Luque 2007;Guidelli et al 2009;Neves et al 2013;Tavares-Dias et al 2013). This mode of dispersion has been associated with the direct life cycle of Monogenoidea parasites, as well as the susceptibility and capacity of immunological response of the hosts (Paraguassú and Luque 2007;Tavares-Dias et al 2013). Dispersion values were lower for species with high prevalence, because aggregation tends to decrease as the proportion of hosts that are infected increases, and parasites spread more evenly among hosts, leaving fewer hosts uninfected (Poulin 1993).…”

“…Although G. leporini in this study had the highest mean intensity of Metazoan parasite communities of Leporinus macrocephalus (Characiformes: Anostomidae) in cultivation systems in the western Amazon, Brazil ACTA AMAZONICA infection in both systems (10.1), they had low prevalence (21.5%), while in southeastern Brazil prevalence was higher (65%), with lower mean infection intensity (4.1) (Martins and Yoshitoshi 2003). The aggregated dispersion of metazoan parasites in L. macrocephalus found in our study is a common pattern in parasite communities of freshwater fish in different regions of Brazil (Machado et al 1996;Abdallah et al 2004;Moreira et al 2005;Paraguassú and Luque 2007;Guidelli et al 2009;Neves et al 2013;Tavares-Dias et al 2013). This mode of dispersion has been associated with the direct life cycle of Monogenoidea parasites, as well as the susceptibility and capacity of immunological response of the hosts (Paraguassú and Luque 2007;Tavares-Dias et al 2013).…”

Ectoparasites as numerical dominant species in parasite community of Trachelyopterus striatulus (Siluriformes: Auchenipteridae) from Guandu River, southeastern Brazil

“…According to Poulin (1996), the host sex influence on parasite prevalence and abundance is a topic hardly touched upon in community analysis discussions, and it is necessary to conduct further experiments which show the influence of other factors mainly on fish physiology and behaviour. Paraguassú and Luque (2007) recorded only Dactylogyridae gen. sp. from a sample of 34 specimens of T. striatulus from Lajes reservoir, Rio de Janeiro, with prevalence values lower than those determined in the present work.…”

“…Only three studies on the parasites of T. striatulus from Brazil were published: Kritsky et al (1995) observed a species of Scleroductus from Guandu river; Moreira et al (2000) described a new species of Cucullanus from State of Minas Gerais, and Paraguassú and Luque (2007) performed preliminary studies on quantitative aspects of the parasites of T. striatulus from Lajes reservoir. Other quantitative studies on parasites of auchenipterid fishes from Brazil is that of Tavernari et al (2009) who studied Auchenipterus osteomystax Miranda Ribeiro, 1918 from two different environments, Rosana's reservoir and the upper Paraná river floodplain.…”

Nematodes in Hoplerytrinus unitaeniatus, Hoplias malabaricus and Pygocentrus nattereri (pisces characiformes) in Marajó Island, Brazil

“…Brazilian data (KOHN et al, 1988;MARTINS et al 2003MARTINS et al , 2005MARTINS et al , 2009MADI;SILVA, 2005;BARROS et al, 2006BARROS et al, , 2007BARROS et al, , 2010PARAGUASSÚ;LUQUE, 2007;VICENTIN, 2009;RODRIGUES, 2010) show that to date, most investigations dealing with parasites of hygiene and sanitary importance in H. unitaeniatus, H. malabaricus or P. nattereri have been conducted on specimens caught in aquatic environments of the Brazilian Amazon region. The only other investigations have been the studies by Martins et al (2005) dealing with H. unitaeniatus and H. malabaricus from the swamplands of the State of Maranhão; Barros et al (2006) with P. nattereri from the metropolitan area of Cuiabá, State of Mato Grosso (MT); Barros et al (2007) with H. malabaricus from the municipality of Santo Antonio do Leverger, MT;and Barros et al (2010) with P. nattereri in the Cuiabá river, municipality of Barão de Melgaço, MT.…”