Vitamin A in poultry. Effects of vitamin deficiency

Abstract

The results of two trials to determine the effects of vitamin A deficiency on fowls and on their progeny are presented. The egg production of the vitamin A deficient groups was 23 per cent. lower than that of the vitamin A adequate controls when the deficiency was first established by liver analyses, 57 per cent. lower when lesions of the deficiency were first apparent by field examination, and finally production ceased. Egg production of pullets that were reversed after field evidence of vitamin A deficiency was established returned to normal two weeks after supplementation with vitamin A. Rearing mortality was 71 per cent. in progeny from deficient pullets when reared on a deficient ration, 41 per cent, in progeny from deficient pullets when reared on a sufficient ration, 17 per cent. in progeny from deficient pullets when reared on a heavily supplemented ration (5x sufficient), 25 per cent. in progeny from sufficient pullets when reared on a deficient ration, and 4 per cent. in progeny from sufficient pullets when reared on a sufficient ration. Most deaths occurred towards the end of the first week of life.