Interaction of nutrition and infection: effect of zinc deficiency on resistance to Trypanosoma musculi.

1. Zinc deficiency was studied in mice infected with Trypanosoma musculi. 2. In all dietary groups, the infected animals consumed more food and gained more weight than the uninfected controls. 3. In all studies, at the peak of parasitemia, the zinc-deficient animals showed three times the number of trypanosomes as that of the complete and pair-fed mice. 4. The average coefficients of variation in body lengths of T.musculi cells indicated that the formation of the reproductive-inhibiting antibody (ablastin) occurred later in zinc-deficient animals compared to animals fed complete diets. The degree and duration of parasitemia in the zinc-deficient animals indicated a delay in the synthesis of the terminal lytic antibody. 5. Irrespective of diets, severe depression in the primary and secondary antibody responses to in vivo immunization of sheep erythrocytes was observed in infected animals over non-infected controls.