The effect of protein malnutrition on the susceptibility of the chicken nose to Newcastle disease virus.

The effect of protein malnutrition on the susceptibility of the chicken nose to Newcastle disease virus (NDV) was studied. Chicks that were rendered acutely protein-deficient for 1 or 3 weeks from the time of hatching yielded approximately 10 times more NDV from their throats than did normally fed animals 7 days after inoculation with the virus. Serum antibody responses in the protein-deficient animals 14 days after inoculation of NDV was statistically lower than in the normally fed animals. These results were supported by the mucociliary transport time in the turbinate and sinus, as well as by the histological changes in the turbinate. This difference may thus be due to the fact that normally fed maturing chicks develop an increased resistance to virus which is depressed in protein-deficient animals.