[Vitamin A requirement of fattening turkeys. 1. Vitamin A requirement of fattening turkeys under conditions of intensive rearing on the ground].

In two experiments with a total of 2,250 fattening turkeys at VEB KIM Turkey and Goose Production Gühlen-Glienicke graded doses of vitamin A (0...20,000 I.U./kg feed) in a ration type poor in vitamin A and carotene were tested in dependence on sex. After a 20-day depletion period the vitamin A supplement of 0, 125 and 250 I.U.vitamin A/kg feed resulted in vitamin A deficiency symptoms after feeding this ration for 1 week. A supplement of between 500 and 1,000 I.U. vitamin A/kg feed diminished consumption in some cases significantly. On the basis of parameters of the fattening performance and of the vitamin A content of the liver it could be proved that the optimal growth of the male and female animals requires approximately 2,000 I.U. and the adequate storage of vitamin A in the liver approximately 5,000 I.U./kg feed. The requirements are fulfilled by the current supplements of the mixed feed for fattening turkeys kept intensively on the ground.