Metacercárias De Austrodiplostomum Compactum (Lutz, 1928) Em Peixes De Lagos De Várzea Da Amazônia Brasileira

Abstract

RESUMOO presente estudo investiga a presença de diplostomídeos parasitas em dois peixes curimatídeos, Potamorhina latior e Potamorhina pristigaster, além de listar todos os peixes reportados como hospedeiros para Austrodiplostomum compactum na Amazônia brasileira. Os peixes foram coletados em oito lagos de várzea do rio Solimões, no período de fevereiro de 2013 a dezembro de 2015. Foram analisados cem indivíduos de P. latior e sessenta e nove indivíduos de P. pristigaster, nos quais foram encontrados nos olhos dois espécimes de A. compactum em P. latior e apenas um espécime em P. pristigaster. Com os novos registros um total de oito espécies de peixes são citadas como hospedeiras para A. compactum na Amazônia brasileira incluindo Acestrorhynchus falcirostris, Cichla monoculus, Plagioscion squamosissimus Pterygoplichthys pardalis e Pygocentrus nattereri. As infecções ocorrem em diferentes órgãos: brânquias, musculatura, mesentério, olhos, gônadas, cavidade visceral e rins. Verifica-se que A. compactum apresenta baixa especificidade pelos hospedeiros e estima-se que os baixos índices parasitários associados a amostras de pequeno tamanho subestimem as diversas outras espécies de peixes amazônicos que albergam estes diplostomídeos. PALAVRAS CHAVE:Austrodiplostomum; Diplostomidae; Lagos de várzea; Parasitos de peixes. AUSTRODIPLOSTOMUM COMPACTUM (LUTZ, 1928) METACERCARIAE IN FISH FROM BRAZILIAN AMAZON FLOODPLAIN LAKES ABSTRACTThis study investigates the presence of diplostomids parasites in two curimatids fish, Potamorhina latior and Potamorhina pristigaster and lists all the fish reported as hosts for Austrodiplostomum compactum in the Brazilian Amazon. Fish were collected in 8 Solimões river floodplain lakes, from February 2013 to December 2015. One hundred individuals of P. latior and sixty-nine individuals of P. pristigaster were analyzed, in which were found two specimens of A. compactum in the eyes of P. latior and only one specimen in the eye of P. pristigaster. With these two new records, a total of eight fish species are cited as hosts species for A. compactum in the Brazilian Amazon including: Acestrorhynchus falcirostris, Cichla monoculus, Plagioscion squamosissimus Pterygoplichthys pardalis and Pygocentrus nattereri. The Infections occur in different organs: gills, muscles, mesentery, eyes, gonads, visceral cavity and kidneys. A. compactum has low specificity for fish host species and it is estimated that low parasitic indices associated with small samples underestimate other Amazonian fish species that harbor these parasites.

Digenea parasites of Acestrorhynchus falcirostris (Osteichthyes, Acestrorhynchidae) in the state of Amazonas, Brazil

“…C. marginatum (Figure 4g) were also recovered from 43.0% (34 out of the 82 fish examined; 1-26 digeneans per fish). A. compactum had already been reported in this host from the state of Amazonas by Vital et al (2016) and C. marginatum from the state of Amapá by Hoshino et al (2016). The material studied were deposited in the "Instituto Nacional de Pesquisas da Amazônia", (INPA), Manaus,Brazil: A. compactum (INPA numbers: 651,652,653,654,655,656) and C. marginatum (INPA numbers: 644,645,646,647,648,649,650).…”

“…Until now, two species of Digenea had been reported in A. falcirostris in Brazil: Metacercariae of Austrodiplostomum compactum Lutz, 1928 in state of Amazonas (VITAL et al, 2016) and Clinostomum marginatum Rudolphi, 1819 in the state of Amapá (HOSHINO et al, 2016).…”

Metacercariae of Austrodiplostomum spp. (Digenea: Diplostomidae) infecting the eyes and brains of fish in Brazilian Amazon

“…The metacercariae of these digeneans that infect the eyes of fish can be found in the retina, vitreous, aqueous, and/or crystalline humor, and also in the brains of hosts. The presence of these metacercariae at heightened levels of abundance can cause exophthalmos, displacement of the retina, opacity of the crystalline lens, blindness, and even the death of host fish (HECKMANN, 1992;BULLARD;OVESTREET, 2008;MONTEIRO et al, 2016;VITAL et al, 2016). The formation of cataracts in infected fish is more intense after the parasites complete their larval development and are ready to infect the definitive host, augmenting the susceptibility of intermediate host fish to predation (SANTOS et al, 2002;PINTO;MELO, 2013;CORRÊA et al, 2014).…”

“…The formation of cataracts in infected fish is more intense after the parasites complete their larval development and are ready to infect the definitive host, augmenting the susceptibility of intermediate host fish to predation (SANTOS et al, 2002;PINTO;MELO, 2013;CORRÊA et al, 2014). This is therefore an efficient transmission method for these digeneans (MOURITSEN;POULIN, 2003;VITAL et al, 2016).…”

“…In Brazil, it has been registered infecting the eyeballs of Geophagus brasiliensis (NOVAES et al, 2006), Geophagus surinamensis (SANTOS et al, 2002), Cichla ocellaris (SANTOS et al, 2002), Cichla sp. (SANTOS et al, 2002), Cichla monoculus (MACHADO et al 2005;VITAL et al 2016), Satanoperca papaterra (MACHADO et al 2005, Hoplias malabaricus (SANTOS et al, 2002;CORRÊA et al, 2014), Hypostomus regani (YAMADA et al, 2008;ZICA et al, 2009), Schizodon borellii, Auchenipterus osteomystax, Serrasalmus maculatus (YAMADA et al, 2008), and Plagioscion squamosissimus (KOHN et al 1995;SANTOS et al, 2002;MACHADO et al, 2005;SANTOS et al, 2002;ALBUQUERQUE et al, 2017), all of which are fish from different ecosystems. Despite the wide distribution and the increasing number of cases of occurrence of these eye fluke infections in Brazilian fish, the possible impacts on wild fish species remain unknown or neglected.…”