In the Territory of Hawaii, protein in concentrate form is at a premium. Soybean and linseed oil meals, cottonseed and peanut meals, all must be imported at high prices. On the other hand urea, which has long been used as a fertilizer in the cane fields, is high in nitrogen and can be stored indefinitely. Should it be possible to replace the nitrogen of protein supplements in whole or in part with urea nitrogen in beef and dairy cattle rations, considerable economie advantage would accrue to the Territory. Various European workers, as reviewed by Krebs (2) and Hart and his associates (1) in this country have conducted feeding trials using various forms of non-protein nitrogen. To our knowledge, only the Wisconsin and Hawaii agricultural experiment stations have made studies over a long growth period. Although the work here reported was begun later than that at Wisconsin, it was begun independently without knowledge of other work being carried on in this country. It is all the more valuable therefore, that the results presented in this preliminary report substantiate those reported by the Wisconsin workers in the 1938 proceedings of this Society, that urea nitrogen can be utilised by the growing dairy animal.