Histological and immunological studies on intermediate host of some trematods

Abstract

Freshwater pulmonate snails are important from both medical and economic views, since they cause various types of diseases to man and other vertebrates. In the present work some aspects of the interrelationships between snail intermediate hosts and their parasites have been studied . Two species of snails., were investigated during this work namely : Biomphalaria alexandrina and Bulinus truncatus which being

the intermediate hosts of schistosom and echinostome parasites.

The present work consists of tn!.ee parts: the first part aims to study the effect of Schistosoma mansoni and Echinostoma sp. on the ovotestis of different sizes of B. alexandrina and B.truncatus respectively. The second part concerns with the effect of the parasites on the neurosecretory cells of investigated samples, in an attempt to give more details on extent of the effect of parasites on the relation between neurosecretory cells and gonad maturation. Therfore, these two parts contain n01mal histological investigation of gonads and neurosecretory cells, which is considered essential in order to permit a recognition of specific pathological alteration which might be induced by the infection. For giving a complementary view of the present work, the third part was carried out to determine any significant changes in tissue glycogen, hemolymph total