Abstract: | Severe granulocytopenia and anemia were developed uniformly in rats fed protein-free diets. Casein (18 per cent) prevented these dyscrasias, but crystalline L. casei factor ("folic acid") did not prevent them. In the correction of granulocytopenia in rats fed protein-free diets, L. casei factor alone was only slightly effective, diets of higher casein content (18 or 30 per cent) were ineffective under the experimental conditions described. However, L. casei factor combined with an 18-per cent casein-containing diet or L. casei factor combined with a mixture of purified amino acids were found to be highly effective in correcting the granulocytopenia. |