Showing papers on "Bulinus truncatus published in 1979"
TL;DR: In this article, a method of measuring the compatibility between schistosomes and the intermediate snail hosts, the total cercarial production per 100 exposed snails, is introduced.
Abstract: The susceptibility of Bulinus truncatus, B. tropicus, B. natalensis, B. coulboisi, B. globosus, B. cernicus and B. wrighti to Schistosoma haematobium from Egypt were examined. Eighteen different populations of B. truncatus were investigated.A new method of measuring the compatibility between schistosomes and the intermediate snail hosts, the total cercarial production per 100 exposed snail, is introduced.All B. truncatus populations became infected and could be divided in four groups according to the total cercarial production per 100 exposed snails. In the first group the cercarial production varied from 250 000 to 500 000 and in the last group between 5000 and 20 000. The first group had a high infection rate of 62 to 100% and a low mortality of approximately 10% and the last group showed a very low infection rate and a high mortality.B. globosus (Rhodesia), B. cernicus and B. wrighti became infected, while B. globosus (Zaire), B. coulboisi, B. natalensis and B. tropicus were refractory.The shortest prepatent period was 26 days at a room temperature of 26°C. The maximum cercariae production for one snail in one day was 600 and the longest duration of infection was 200 days.Experimenting with different doses of miracidia, 5 to 50 per snail, resulted in a one hundred per cent infection and a low mortality of 10%. There was only a slight variation in the cercarial production.
36 citations
TL;DR: In this paper, a system of standards using the enzyme phenotype of Bulinus truncatus as reference is described and brief mention is made of the promising results obtained so far by the application of the method on the taxonomy and identification of the Bulinus species from Kenya.
22 citations
TL;DR: The reproductive tract of B. truncatus was investigated histologically in order to study possible effects of castration upon the accessory sex glands and the abundance and location of the cell types were taken into account.
Abstract: The reproductive tract of B. truncatus was investigated histologically in order to study possible effects of castration upon the accessory sex glands. In the female part of the reproductive tract—subdivided into albumen gland, oviduct, muciparous gland, oothecal gland, uterus, vagina and bursa copulatrix—13 histochemically different secretory cell types were distinguished. The majority produce different types of (acid) mucopolysaccharides. The roles of the various parts of the female tract in the production of an egg mass were elucidated by comparing the histochemistry of the egg mass to that of the female tract; the abundance and location of the cell types were also taken into account for this purpose. The male part appeared to contain 12 histochemically different secretory cell types. These produce mainly (phospho lipoproteins together with some polysaccharides and neutral lipids. Castration causes an acceleration of the growth of the snails. The volumes of female (albumen gland) and male (prostate glan...
20 citations
TL;DR: Schistosoma bovis from Morocco was used in infection experiments with several populations of Bulinus truncatus and the snails from Libya, Malawi, Morocco and Senegal were very compatible with the schistosome, and B. forskalii were refractory.
Abstract: Schistosoma bovis from Morocco was used in infection experiments with several populations of Bulinus truncatus. The snails from Libya, Malawi, Morocco and Senegal were very compatible with the schistosome since the infection rates were approximately 90%, the mortality was low, and a very high production of cercariae, approximately 1.2 million per 100 exposed snails, was observed. Only a very few B. truncatus (2n = 36) from Rhodesia became infected. B. permembranaceus and B. forskalii were refractory.
20 citations
Journal Article•
TL;DR: A preliminary biological screening for molluscicidal activity of certain Sudanese plants used in Folk-medicine showed that the petroleum ether extracts of only 4 samples were active against Bulinus truncatus; while the alcoholic extracts of 16 samples were found to be active against the same snail species.
Abstract: A preliminary biological screening for molluscicidal activity of certain Sudanese plants used in Folk-medicine was carried out. 78 samples belonging to 51 species, 45 genera and 28 families were screened. The aqueous extracts of 18 samples belonging to 8 species, 6 genera and 5 families were found to be active against Bulinus truncatus and 7 of these were also found to be active against Biomphalaria pfeifferi. Successive extraction of the 18 active samples with petroleum ether, ethanol and water showed that the petroleum ether extracts of only 4 samples were active against Bulinus truncatus; while the alcoholic extracts of 16 samples were found to be active against the same snail species. Only the alcoholic extracts of 4 samples were proved to be active against Biomphalaria pfeifferi. In the successive extraction technique, only the aqueous extract of Gardenia vogelii fruit pulp was proved to be active against the two snail species tested.
12 citations
TL;DR: Two collections of Bulinus truncatus (Audouin) have been subjected to laboratory rearing, bioassay and measurement of the rate of uptake of the chemical into the snail and a difference in susceptibility could be shown.
Abstract: Chemical control of the intermediate hosts of schistosomiasis, based on copper sulphate, has been practised in the Sudan Gezira since 1956. A continued use of the more recent trifenmorph blanket-treatments raises the question of eventual resistance to this molluscicide. Two collections of Bulinus truncatus (Audouin), from a treated and an untreated area of the Gezira, have therefore been subjected to laboratory rearing, bioassay and measurement of the rate of uptake of the chemical into the snail. A difference in susceptibility could be shown and this has been tentatively attributed to the rather more marked difference, in penetration rate of the molluscicide, between the two groups of snails.
7 citations
TL;DR: The susceptibility of Bulinus truncatus, the snail vector of Schistosoma haematobium to the molluscicides Bayluscide and Mollutox, was studied by measuring the respiration rate of young and older snails at 20° and 30°.
Abstract: The susceptibility of Bulinus truncatus, the snail vector of Schistosoma haematobium to the molluscicides Bayluscide and Mollutox, was studied by measuring the respiration rate of young and older snails at 20° and 30°. The results are discussed and their importance on application of mollusciceds indicated.
3 citations
Journal Article•
TL;DR: Under the chosen experimental conditions H. duryi revealed higher tolerance limits and survival rates than B. alexandrina and B. truncatus, and as biological control agent of Schistosome vector snails is discussed.
Abstract: The influence of 10 degrees, 18 degrees, 26 degrees, 28 degrees and 33 degrees C, different periods of complete darkness and starvation on growth and survival of H. duryi, B. alexandrina and B. truncatus were studied. The optimum temperature for the growth and survival was about 26 degrees C. Survivorship and growth rates decreased proportionately according to starvation period. However, darkness had no significant effect on the growth of B. truncatus and H. duryi. Under the chosen experimental conditions H. duryi revealed higher tolerance limits and survival rates than B. alexandrina and B. truncatus. The potential of H. duryi as biological control agent of Schistosome vector snails is discussed.
2 citations