The Development of a Ration for the Study of Perosis in Chicks

PEROSIS is a type of leg weakness and deformity which occurs among rapidly growing chicks, particularly when they are confined in battery brooders and on rations high in minerals. The other common name for perosis is “slipped tendon.” High inorganic phosphate additions to the ration are admitted to be a contributing cause of the trouble, although it is also stated in the literature that a high level of calcium carbonate may contribute to the development of perosis. Descriptions of the character of the deformity and attempts to correct it have been reviewed by Milby (1934) and Wilgus, Norris, and Heuser (1935). A variety of rations has been used by different investigators for the production of this deficiency, but in general some form of a practical ration has been used. Since we frequently observed slipped tendon in chicks grown on some of our synthetic diets, we were interested to learn if . . .