Ultraviolet radiation of schistosoma mansoni. I. influence of pre-hatching radiation of eggs on hatchability of eggs and survival of miracidia

Abstract

The hatchability of Schistosoma mansoni' eggs exposed to ultraviolet (UV) radiation and the activity of die hatched miracidia were examined. Hatchability decreased with die increasing exposure to irradiation. The difference in hatchability of eggs irradiated for 15 and 30 minutes were highly significant (P < 0.01. dα = 3.07 and 3.24) compared with hatchability of the non-irradiated eggs. The mean motility rates of the hatched m iracidia were found to be radiation dose-dependent. There was a 21.4% reduction in motility compared with die motility rates in the non-irradiated miracidia. The life span of irradiated miracidia was shortened, only 19% of dtose exposed to UV radiation for 30 minutes survived for 3 hours as against 80% survival rate in die non-irradiated miracidia. There was no significant difference found in the ability of hatched miracidia to attach to the snails irrespective of the radiation dose exposure the eggs were initially subjected