Digestive disturbance is the most common of all the ailments of dairy calves, and is the forerunner of pneumonia and navel infection in a large proportion of the calves which develop these troubles. Digestive disturbance should lead to a suspicion of improper diet, and it is rather surprising that the factors of infection, management, and housing have so long overshadowed this factor of diet. Many calves develop scours while nursing, but improper diet is probably the chief cause of digestive disturbance even in these calves.