Compatibility of &amp;lt;i&amp;gt;Biomphalaria glabrata&amp;lt;/i&amp;gt; and &amp;lt;i&amp;gt;B. alexandrina&amp;lt;/i&amp;gt; snails to infection with an egyptian strain of &amp;lt;i&amp;gt;Schistosoma mansoni&amp;lt;/i&amp;gt; through two cycles in the experimental final host

Momeana Bayoumi Mahmoud

doi:10.4236/abc.2011.13012

Abstract

The infection rate and cercarial production from B. glabrata, in comparison with B. alexandrina snails, post their exposure to S. mansoni miracidia of an E- gyptian strain after two cycles in albino-mice was stu-dies.The results indicated that infection rate of B. glabrata with the Egyptian strain of S. mansoni was less than that of B. alexandrina snails On the other hand infected B. glabrata exhibited a longer life span and a higher number of shedding cercariae, It was also, noticed that in the first cycle mice infected with S. mansoni cercariae shed from infected B. alexandrina snails, the mean number of worms recovered from infected mice was approximately twice that in mice infected with cercariae shed from infected B. glabrata snails The same observation was recorded from the mean number of ova/g liver tissue from infected mice. In the second cycle the same observation was recorded as first cycle suppression in the infection rate of B.glabrata than that B.alexandrina. Also, longer pre-patent period and life span Also, mice infection as the number of worms per infected mouse by cercariae shed from B.alexandrina snails was approximately 2.5 times that of mice infected by cercariae shed from B. glabrata being 29.3 and 12.5 worms/mouse.The results also indicated that the egg laying capacity of B. glabrata was higher than that B. alexandrina, It is concluded from this work that infectivity of S. man-soni cercariae shed from B. glabrata snails after two cycles of mice infection and used to infect the experi-mental final host was less than that of cercariae shed from infected B. alexandrina snails. This may declare a low compatibility of B. glabrata snails with the Egyptian strain of S. mansoni in comparison with B. alexandrina snails. However, this conclusion needs more passages of mice infection with cercariae to have precise data and conclusions.

Highlights

Schistosomiasis is one of the major health problems in many developing countries [1]
Longer prepatent period and life span mice infection as the number of worms per infected mouse by cercariae shed from B. alexandrina snails was approximately 2.5 times that of mice infected by cercariae shed from B. glabrata being 29.3 and 12.5 worms/mouse.The results indicated that the egg laying capacity of B. glabrata was higher than that B. alexandrina, It is concluded from this work that infectivity of S. mansoni cercariae shed from B. glabrata snails after two cycles of mice infection and used to infect the experimental final host was less than that of cercariae shed from infected B. alexandrina snails
The present study aims to study the compatibility of B. glabrata snails to infection with an Egyptian strain of S. mansoni which is very important from the epidemiological point of view and draws the attention to the possible role of this snail (B. glabrata) may play in schistosomiasis in Egypt

Summary

INTRODUCTION

Schistosomiasis is one of the major health problems in many developing countries [1] The prevalence of this parasite in human population depends on the number of infected snails in an area. The specificity of parasite-host interactions has received great attention by parasitologists and evolutionary biologists [2] It was known till 1996 that B. alexandrina is the only planorbid species acting as the intermediate host of Schistosoma mansoni in Egypt. Host snails of the genus Bomphalaria respond with humoral and cellular mechanisms to S. mansoni sporocysts [7] It was recently demonstrated by selection experiments under laboratory conditions with different snail lines that, in the system S. mansoni, B. glabrata, compatibility characteristics seem to be inherited with resistance being dominant over susceptibility [4,8]. The present study aims to study the compatibility of B. glabrata snails to infection with an Egyptian strain of S. mansoni which is very important from the epidemiological point of view and draws the attention to the possible role of this snail (B. glabrata) may play in schistosomiasis in Egypt

Snails

Snails Infection

Animals Infections

Parasitological Investigations

First Cycle