Vitamin A deficiency in the domestic fowl

Abstract

Young male chicks (Light Sussex breed) placed on a vitamin A-deficient diet became unsteady on their legs in the 4th week and soon afterwards died. The kidneys were pale and showed deposits of urates. There was, however, no loss of appetite or weight, no xerophthalmia or lesions in the tracea or esophagus. Older birds (Brown Leghorn breed) of both sexes were put on a vitamin A-deficient diet at 16 weeks of age. Control birds were given vitamin A as a supplement. Deficiency symptoms began to appear after 7 weeks of deprivation; the males suffered recurring brief loss of consciousness and the females found difficulty in standing. Epithelial lesions were a late symptom. Sexual development was greatly retarded in both sexes. Various tissues (liver, kidney, intestine) were obtained from the young chicks and from control birds and the unsaponifiable fractions were examined by chromatographic and spectrophoto-metric methods. The rise in SA and SC (2 spectroscopically recognizable compounds of unknown composition) which occurs in vitamin A-deficient rat tissue did not appear in the chick tissues. Similar study of tissues (liver, kidney, intestine, gizzard, esophagus and crop, trachea) from older birds of both sexes made vitamin A deficient revealed no real difference in respect to SA, SC, total sterol, 7-dehydrocholesterol and cholesta-3:5-dien-7-one between the controls and the deprived birds. Preliminary work on gizzard muscle and lining showed the presence of cholesta-3:5-dien-7-one in both tissues.