'Trichostrongylus vitrinus' infection in Australian meat sheep: Partitioning cost of infection to direct and host immune-mediated components

Abstract

Background: Immune suppression with methylprednisolone alleviates depression of weight gain following infection with 'Teladorsagia circumcincta' or 'Trichostrongylus colubriformis', which suggests that host immune response rather than direct parasite damage is the major cause of lost productivity. To test this for 'Trichostrongylus vitrinus' infections we estimated the overall cost of infection (CI) in terms of lamb growth, and a component of it, the cost of host immune response (CIR) in Poll Dorset x Border Leicester-Merino lambs.