The Occurrence of Leg Weakness in Mature Turkeys1

SCOTT (1950), reported that the oc-currence of enlarged hocks at 2 to 4 weeks of age in turkey poults increased the incidence of leg weakness or perosis in ma-ture turkeys. Later, Scott (1953) demon-strated that the addition of 30 mg. of niacin and 5 mg. of alpha tocopheryl ace-tate per pound of feed completely prevented the early condition. Also, the addition of the same level of alpha tocopheryl acetate and 20 mg. of niacin per pound to the de-veloping ration prevented the mature leg condition in turkeys that showed a high in-cidence of the leg abnormalities as poults. Single supplementation of niacin or alpha tocopheryl acetate to the developing diet had no beneficial effect. Slinger et al. (1954) fed starting and developing mashes containing all combina-tions of 0.3, 0.5 and 0.7 percent inorganic phosphorus and 0, 2.5, 5.0 and 7.5 I.U. of vitamin E per pound. Vitamin E and phosphorus reduced the incidence and severity of perosis in the turkeys at 24 weeks of age. The most efficient levels of inorganic phosphorus and vitamine E were found to be 0.7 percent and 5.0 I.U., re-spectively. In later work, Slinger et al. (1955) found that 0.5 percent inorganic phosphorus was adequate in the developing mash, provided that 0.7 percent inorganic phosphorus had been supplied in the diet from hatching to 8 weeks of age. Vitamin E also prevented (or helped prevent) perosis in the matur