Plasma zinc and inappetence in sheep infected with Trichostrongylus colubriformis.

The concentration of zinc in plasma before and after the occurrence of inappetence was measured in sheep infected with Trichostrongylus colubriformis and in uninfected animals fed freely or pair-fed with the infected group. Infection reduced mean food consumption to about one-third of that of the sheep fed ad libitum, half becoming completely anorexic. Plasma zinc concentrations in the infected sheep were reduced by 17 per cent whereas they were unchanged in the uninfected groups.