Exsheathment of infective larvae of Cooperia curticei

Abstract

Extract

Although exsheathment of the infective larvae of many strongylate nematode parasites of ruminants has been studied (Rogers, 1966 Rogers, W. P. 1966. “Exsheathment and hatching mechanisms in helminths”. In Biology of Parasites, Emphasis on Veterinary Parasites, Edited by: Soulsby, E. J. L. 33–39. New York and London: Academic Press. In Google Scholar]), that of Cooperia curticei larvae has not. By analogy with other trichostrongylid species inhabiting the small intestine, they would be expected to exsheath in response to conditions provided by the abomasum, perhaps, as with Trichostrongylus colubriformis, with a potentiating effect of bile salts in the small intestine (Mapes, 1972 Mapes, C. J. 1972. Bile and bile salts and exsheathment of the intestinal nematodes Trichostrongylus colubriformis and Nematodirus battus. Int. J. Parasit., 2: 433–438.  Google Scholar]). It was decided to see if C. curticei larvae exsheathed as expected; no attempt was made to define precisely the conditions necessary for exsheathment but rather to establish the site at which the stimulus is received.