Effect of Niclosamide (Bayluscide WP 70 (R)), Anacardium occidentale hexane extract and Euphorbia splendens latex on behavior of Biomphalaria glabrata (Say, 1818), under laboratory conditions

Abstract

The repellent effect of the molluscicides Niclosamide (Bayluscide WP 70), Anacardium occidentale and the latex of Euphorbia splendens on Biomphalaria glabrata was observed through the investigation of the occurrence of escape behavior among molluscs that were exposed to dosages lower than the LD 50. The total number of individuals out of water among the surviving snails in the control group provided a "Natural Escape Index". The comparison between this total and the total number of surviving snails in each group exposed to the different dosages of the molluscicides after 24 hr provided the "Molluscicide Escape Index" and the detection of a "Repellency Range" to these snails. The escape indexes for Niclosamide, A. occidentale and E. splendens were 10%, 6.22% and 6.44% respectively. Repellency occurred at the following concentration ranges: 0.01, 0.02 and 0.03 ppm Bayluscide, 0.1, 0.2 and 0.3 ppm A. occidentale and 0.05, 0.10, 0.15 and 0.20 ppm E. splendens. The Natural Escape Index obtained in the control group was zero.

Effects of Bayluscide WP 70® on the Survival and Water-leaving Behaviour of Biomphalaria straminea, Snail Host of Schistosomiasis in Northeast Brazil

“…These results are in constrast with those obtained for B. glabrata by Jurberg et al (1995), who found a repellency range between 0.01 mg/l and 0.03 mg/ l of niclosamide, and no water-leaving behaviour in the control group. Since the present study followed the same procedures as that by the above authors, it can be concluded that B. straminea is more liable to leave the water than B. glabrata irrespective of the presence of sublethal doses of niclosamide.…”

“…In the behaviour assay at least 30 snails were used in each dose. After the exposure period the snails found out of the water in each dose of the behaviour assay were identified and counted for calculating the escape index (Jurberg et al 1995). All snails were then rinsed and placed in individual 250 ml glass vials containing 100 ml of dechlorinated filtered tapwater and fresh lettuce, and allowed to recover in the environmental chambers for 24 hr before being checked for mortality.…”

Gross histopathological effects of an extract of Agave attenuata on the epithelium of the digestive tract of Bulinus africanus

“…africanus exposed to the extract were similar to those made in other pulmonate species after exposure to copper and other plant molluscicides (Harry and Aldrich, 1963;Sullivan and Cheng, 1975;Van Aardt and Coertze, 1981;Adewunmi and Ogbe, 1986;Jurberg et al , 1995;Bode et al , 1996) and all have been taken to indicate disruption of the external epithelial membrane. A study by Brackenbury and Appleton (1999) on the foot-sole epithelium of Bu.…”

A laboratory assessment of the potential molluscicidal activity of some Nigerian plant species used as anthelmintics

“…Immobility, complete retraction into the shell and hypersecretion of mucus prior to death, as observed in snails exposed to lethal concentrations of extracts in the present study, are indicators of molluscicidal poisoning (Nolan et al 1953, Sullivan and Cheng 1975, van Aardt and Coertze 1981, Adewunmi and Ogbe 1986, Evans et al 1986, Duncan 1987, Pretorius et al 1991, Jurberg et al 1995, Bode et al 1996. This is without prejudice to the 'supposed temporary protection' which the mucus appeared to offer by impeding snail contact with the extracts, as it blocked the shell aperture while the viscera were retracted within the shell.…”