So, understanding the changes in the reproductive biology of snails infected with A. cantonensis HIF cancer is essential for developing effective methods against the spread of human eosinophilic meningoencephalitis. However, it is surprising that studies of the reproductive activity of A. cantonensis-infected snails

have not yet been conducted, since this parasite has great importance to public health and the response to infection is highly variable among snail species infected by different helminths ( Tunholi et al., 2011). To shed light on this subject, the present study analyzed for the first time, the changes in the reproductive biology of Biomphalaria glabrata caused by infection by A. cantonensis during its prepatent period (3 weeks of infection) ( Guilhon and Gaalon, 1969), using the parameters total number of eggs, number of egg masses, number of eggs/mass, number of eggs/snail, percentage of viable eggs, and galactogen content in albumen gland, as well as the histological status of the gonad (ovotestis of infected snails). The different mechanisms possibly related to this phenomenon are also discussed. The snails were kept in aquariums containing 1500 ml of dechlorinated water, to which 0.5 g of CaCO3 was added. Polystyrene plates measuring ±2 cm2 were placed inside the aquariums to serve as substrate for egg laying. The snails were fed with dehydrated lettuce leaves

(Lactuca sativa L.) ad this website libitum. Six groups were formed: three control groups (uninfected) and three treatment groups (infected). Each aquarium contained 10 snails, reared Ceramide glucosyltransferase in the laboratory from hatching to be certain of their age and sexual maturity. The entire experiment was conducted in duplicate, using a total of 120 snails. Third-stage larvae (L3) of A. cantonensis, obtained

from specimens of Achatina fulica collected from Olinda, Pernambuco, Brazil (8°1′0″S/34°51′0″W, altitude 16 m) in 2008, in the area surrounding the home of a human patient diagnosed with eosinophilic meningoencephalitis, were inoculated in Rattus norvegicus in the Laboratório Nacional de Referência em Malacologia Médica and Laboratório de Patologia do Instituto Oswaldo Cruz (Fiocruz, RJ, Brazil), where the cycle is maintained. The first-stage larva (L1) utilized in this study were obtained from this experimental cycle maintained in the mentioned laboratories. The feces of parasitized R. norvergicus were collected to obtain the larvae by the technique of Baermann ( Willcox and Coura, 1989). After processing the fecal samples, specimens of B. glabrata (8–12 mm) at 90 days old on average were exposed individually to approximately 1200 L1 larvae ( Yousif and Lammler, 1977). After 48 h the snails were transferred to the aquariums. The polystyrene plates were removed from the aquariums and the numbers of egg masses and eggs laid were counted under a stereoscopic microscope on alternate days until three weeks after infection.