Resistance of helisoma duryi to infection by schistosoma mansoni after exposure to intense radiation

ABSTRACT

The effect of radiation as a stressing factor on the larval development of S.mansoni, Delta strain in H.duryi snails as judged by histopathological examinations as well as the effect of radiation on the infection rate and cercarial production in both B. alexandria and H. duryi was investigated. Snails exposed to two total radiation doses 2000 and 4000 rad/snail 24 hours prior to infection by S.mansoni. The obtained results revealed that no single snail of Helisoma emerged cercariae. As regards B.alexandrina snails, groups exposed to radiation were associated with higher infection rate and more cercarial count than the control group. Histopathological examinations revealed some developmental stages up to mother and daughter sporocysts followed by deterioration with ultimate destruction and removal by phagocytosis indicating that Helisoma is still resistant to infection after exposure to intense radiation