Does the trematode Centrocestus formosanus affect the locomotory activity of the mollusc Melanoides tuberculatus?

Abstract

BackgroundMelanoides tuberculatus (Müller, 1774) (Thiaridae), an introduced gastropod mollusc with a wide geographical distribution in the Neotropics, is the intermediate host of the trematode Centrocestus formosanus (Nishigori, 1924) (Heterophyidae). This parasite is considered to be pathogenic to humans. The aim of the present work was to evaluate the locomotory activity of uninfected M. tuberculatus compared with those naturally infected with C. formosanus.FindingsThe locomotory activity of each mollusc was recorded using an image analysis biomonitoring system, Videomex-V ®, to evaluate and quantify the parameters of ‘Stereotypic’ and ‘Resting time’. The Generalized Estimating Equation analysis of locomotory activity of M. tuberculatus infected with C. formosanus revealed significant differences compared with uninfected molluscs for the parameters ‘Stereotypic time’ and ‘Resting time’ with a reduction of movement. The variations in the values of the monitoring intervals recorded showed a significant difference for the infected molluscs in the case of Stereotypic time, with an irregular locomotory activity pattern, as compared to that of uninfected molluscs. The analysis of the standard length of all molluscs did not exhibit any correlation with locomotory activity, showing that C. formosanus is able to alter the locomotory activity of its snail host regardless of the standard length.ConclusionsThe trematode C. formosanus affects the locomotory activity of the mollusc M. tuberculatus by reducing its movement and causing it to exhibit an irregular pattern of activity, both of which are independent of the snail's standard length.

Current Knowledge of Small Flukes (Digenea: Heterophyidae) from South America

“…Centrocestus formosanus Nishigori, 1924, a species considered of zoonotic importance, was introduced in the Americas within its host snail Melanoides tuberculata. It has been reported from Brazil [43][44][45][46][47], Colombia [48], Peru [50] and Venezuela [51]. The life-cycle includes naturally infected fish (metacercariae in the gills) and birds (adults in the intestine) and experimental infections were performed with G. gallus [45] (Table 1).…”

“…The heterophyid trematode C. formosanus was introduced into Brazil with the gastropod Melanoides tuberculata, which has a wide geographic distribution in the Neotropics [47]. This species, which is considered to have zoonotic potencial, is able to alter the locomotory activity of its snail host regardless of the standard length [47].…”

Centrocestus formosanus (Trematoda: Heterophyidae) in Melanoides tuberculata (Gastropoda: Thiaridae) from Vila do Abraão, Ilha Grande, Rio de Janeiro, Brazil

“…Pleurolophocercous cercariae were firstly recorded in M. tuberculata in the state of Rio de Janeiro (Boaventura et al, 2002;Bogéa et al, 2005;Thiengo et al, 2001) and later, similar larvae were found in Minas Gerais state, which were identified as the heterophyid trematode Centrocestus formosanus (Nishigori, 1924), for the first time in Brazil (Pinto and Melo, 2010). This species was also found parasitizing M. tuberculata in the Federal District (Paula-Andrade et al, 2012) and in the states of Rio Grande do Norte (Pinto and Melo, 2012c) and Rio de Janeiro (Santos et al, 2013).…”

“…To date, it has been reported from 19 states and from the Federal District (Fernandez et al, 2003;Rocha-Miranda and Martins-Silva, 2006;Santos et al, 2013;Thiengo et al, 2007). The species is associated with ecological problems, such as the modification of the community structure caused by the high population densities that it may reach (Santos and Eskinazi-Sant'Anna, 2010;Santos et al, 2012).…”

The life cycle of a zoonotic parasite reassessed: Experimental infection of Melanoides tuberculata (Mollusca: Thiaridae) with Centrocestus formosanus (Trematoda: Heterophyidae)

“…In addition, new studies have reported the interaction of C . formosanus with various hosts, both naturally-infected snails [ 16 ] and experimentally-infected fish, amphibians and rodents [ 17 – 20 ]. Moreover, several studies related to treatment, control, and monitoring strategies for aquatic ecosystems were performed in the last several years [ 21 – 24 ].…”