Host-dependent variation in the morphology of female Ostertagia circumcincta (Stadelmann, 1894) Ransom, 1907, a nematode parasite of sheep

Abstract

Populations of Ostertagia circumcincta from three lambs with different experiences of infection are described. The female worm length, development of the vulva1 flap and number of eggs in the uterus are recorded and correlated with the immune status of the host. Because of the large morphological variation encountered in normal infections it is suggested that, wherever possible, a short grazing history (or details of infection) accompany any description of specimens.Iutroduction

Estimation of Surface Area and Volume of a Nematode from Morphometric Data

“…Nematodes vary greatly in morphology between species [ 7 – 9 ] and life cycle stages, and the morphology of parasitic nematodes can depend on the host [ 10 ]. For example, L 3 Teladorsagia circumcincta essentially has a cylindrical body tapering to relatively pointed ends, the posterior tip being more pointed than the anterior [ 8 , 11 ].…”