Abstract:
When freshly-collected, exsheathed infective larvae of Oesophagostomum columbianum and Chabertia ovina were frozen in liquid nitrogen and subsequently thawed, conspicuous vesicles appeared in the intestinal cells of the larvae. The mean number of vesicles, which differed in size according to the species was 20 for O. columbianum and 32 for C. ovina.