Experimental Host-parasite Relationship Studies with Oesophagostomum columbianum in Sheep : I—Attempts to Establish Infection by Different Routes

Abstract

Attempts to infect lambs cutaneously with O. columbianum failed. Ensheathed larvae exsheathed, grew, moulted to fourth stage and lived several months when injected subcutaneously or intraperitoneally in susceptible lambs. A limited migration occurred and some larvae entered the lungs. No evidence of tracheal migration was seen. Fourth stage larvae failed to reach patency when administered orally to lambs. Prior subcutaneous infection appeared to predispose to larval retention following oral challenge infections