A technique for in vivo labelling of Fasciola hepatica Miracidia with Radioselenium

Abstract

Radioactivity is incorporated in Fasciola hepatica and its eggs when ⁷⁵Semethionine is administered intraperitoneally in chronically infected mice. Maximum egg-bound radioactivity is achieved 2–3 days after the administration of the labelled aminoacid. Seventy-three per cent of the radioactivity of the egg is recovered in the free-swimming miracidium. There appears to be no altered motility or infectivity to snails of miracidia made radioactive at a level corresponding to 6 pCi per larva. Suggestions are made for the application of labelled larvae in studies on various aspects of the parasite-snail contact.