Fatores que podem afetar a criação e manutenção de caramujos infectados e a produção de cercárias de Schistosoma masoni

Abstract

Mass production of Schistosoma mansoni cercariae was affected by biological and chemical agents. Rotifers and ostracods, snail predators, were identified in our colony. Rotifers were easily eradicated by washing the aquaria and lettuce with diluted solution of acetic acid. On the other hand, ostracods were difficult to eradicate and led to a high level mortality of infected snails (50-60%). Snails maintained in an incubator at constant temperature and total darkness produced maximum shedding when submitted to brightness and high temperature (about 30 degrees C). The number of cercariae shed was practically the same between pH 5-7. Contaminants such as Cu and Pb added to glass distilled water decreased the cercariae production. In conclusion, laboratory maintenance of large number of infected snails for mass production of cercariae is much simpler and more efficient than the conventional technique with running tap water although a high rate of mortality is observed in the snail colony.

Rearing of Lymnaea columella (Say, 1817), intermediate host of Fasciola hepatica (Linnaeus, 1758)

“…In the present study, the methodology used to rear L. columella in the laboratory was the same as that used for B. glabrata mass growing (Souza et al 1985(Souza et al , 1987, with satisfactory results (Tables I, II). Initially, in addition to lettuce and powered ration, algae and the aquatic plant (Lemna sp.)…”

“…The snails in aquarium A were fed fresh lettuce and in B, fresh lettuce plus rodent powered ration (Purina®) + 10% CaCO 3 ; the latter diet has already been used to feed Biomphalaria in our laboratory (Souza et al 1985(Souza et al , 1987. The paste ration was placed on the lettuce leaves.…”

The Use of Reverse Vaccinology and Molecular Modeling Associated with Cell Proliferation Stimulation Approach to Select Promiscuous Epitopes from Schistosoma mansoni

“…Traditionally, vaccines have been developed by isolating and purifying antigenic components from a pathogen of interest, which is usually killed by heat or chemically inactivated. This model, however, does not apply to schistosomiasis, since irradiated cercariae presents a high risk of contamination during immunization [6]. Antigens tested in animals have shown promising potential for inducing protection as proteins Sm14, Sm28-GST, Sm97, TPI, IrV-5, Sm23, and Smp80.…”

Evaluation of the Schistosoma mansoni Y-box-binding protein (SMYB1) potential as a vaccine candidate against schistosomiasis

“…Irradiated cercariae used for immunization in experimental animal models regularly induce >80% of protection (Souza et al, 1987; Lin et al, 2011; Tian et al, 2013). However, although some promising antigens have been identified and tested in clinical trials, no effective vaccine against schistosomiasis is currently available.…”