Reproductive activity alterations on the Biomphalaria glabrata exposed to Euphorbia splendens var. hislopii latex

Abstract

The reproductive activity of Biomphalaria glabrata exposed to Euphorbia splendens var. hislopii latex was evaluated. Parameters related to fecundity and fertility were observed. The snails were exposed to the LD 50 (1 mg/l) of crude latex. At the first week post exposure (p.e.) (Magalhães & Lucca 1971, Kawazoe 1977.The physiological stress factors, as temperature variations (Pimentel-Souza et al. 1990), lightness (Barbosa et al. 1987), starvation (Livingstone & Zwaan 1983), and parasitism by larval trematodes (Looker & Etges 1979, Sullivan et al. 1985, Cooper et al. 1994, Cousin et al. 1995 have been pointed as able to influence the reproductive biology of the snails.There are few studies on the interference of plants that exhibit moluscicide action with the reproductive activity of the snails, intermediate host of helminthes. The reproductive capacity of B. alexandrina is reduced when it was exposed to Allium sativum, A. cepa, and Atriplex halimus (Mantawy 2001, Tanatawy 2002.Many molluscicide have been used to schistosomiasis control, and one of the most promising and widely studied in Brazil, is the crude latex of Euphorbia splendens var. hislopii. The latex obtained from this plant, under laboratory and field conditions, showed that it attends to queries needed to be used as a natural molluscicide (Schall et al. 2001, Vasconcelllos & Amorim 2003.The lethal effects on the embryos in the egg masses were obtained using elevated concentrations of the latex (870 a 1500 mg/l) (Schall et al. 1998), but, until the moment, there were no studies focusing the latex effects on the reproductive biology of B. glabrata.The objective of this study was evaluating the influence of sub lethal dose (LD 50 ) of latex of E. splendens var. hislopii on reproductive parameters of B. glabrata. MATERIALS AND METHODSCollection of E. splendens var. hislopii latex -Samples of E. splendens var. hislopii latex were collected in the autumn from plants cultivated in plots near Departamento de Biologia, Instituto Oswaldo Cruz-Fiocruz, Rio de Janeiro, RJ, Brazil. The latex was collected as described by Vasconcellos and Amorim (2003a), on the same day of tests conduction.Rearing of B. glabrata in the laboratory -Specimens of B. glabrata (Belo Horizonte, BH lineage) were reared at the Laboratório de Esquistossomose Experimental, Instituto Oswaldo Cruz-Fiocruz, RJ, Brazil. The snails were placed in 30 l polyethylene aquaria, with dechlorinated water. The average water temperature was 28 ± 1 o C and relative humidity varied from 70 to 78% throughout the experiment.Three times a week the aquaria were cleaned and the snails were fed ad libitum with lettuce leaves (Lactuca sativa L.). All the specimens of B. glabrata used in the experiments had shell diameters between 8-10 mm and exhibit ovipository activity.Determination of sublethal concentrations of latex of E. splendens var. hislopii -The determination of LD 50 were made according to Vasconcellos and Amorim (2003a), in accordance to WHO recommendations (WHO 1983) and Mott (1987) Reproductive ...

Impact of Taraxerol in combination with extract of Euphorbia tirucalli plant on biological parameters of Lymnaea acuminata

“…SUKUMARAN et al 27,28,29 also reported the n-butanol extracts of some plant molluscicides like Sapindus trifoliatus, Agave americana, Balanites aegyptica, Jatropha gossypifolia, and Vaccaria pyramidata are as toxic against freshly laid eggs of L. luteola. MOSTAFA & TANTAWY 14 also found a significant reduction in the hatchability of egg masses of snail Biomphalaria alexandrina after exposure to Calendula micrantha and Anagallis arvensis plant and reduction in the hatching of the snails, revealing an interference of latex exposure with the reproductive process of B. glabrata 13 .…”

Carbohydrate metabolism alterations in Biomphalaria glabrata infected with Schistosoma mansoni and exposed to Euphorbia splendens var. hislopii latex

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OVICIDAL EFFECT OF PIPERACEAE SPECIES ON Biomphalaria glabrata, Schistosoma mansoni HOST

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