The Effect of Vitamin A Deficiency and Newcastle Disease on Lymphoid Cell Systems in Chickens

Abstract

A diet without vitamin A but otherwise nutritionally complete was given to chicks from time of hatching. Control diets with adequate vitamin A were given to two other groups. At age 21 days, Newcastle disease virus (NDV) was nasally inoculated into all 3 groups; controls of each group remained uninoculated. Between Days 1 and 3 after NDV inoculation the A-depleted chicks showed significant loss of lymphocytes from the cortex of both the thymus and the bursa of Fabricius, while those on control diets did not show any loss. On Days 5 to 9, there were minimal to moderate effects on populations of lymphocytes in these organs of the group of chicks given adequate vitamin A, but consistently much more severe effects became apparent in the A-depleted group in which 3 of 7 (42%) of the cortices were essentially devoid of lymphocytes. Granulocytes were prominent in areas of thymic and bursal cortex depleted lymphocytes. Noninfected A-deprived chicks and chicks on a normal diet showed relatively modest depletion of cortical lymphocytes from both organs beginning 5 days after NDV infection.