Non-Protein Nitrogen Studies in Laying Hens

Four experiments were conducted with laying hens to examine the effectiveness of non-protein nitrogen supplementation. Significant increases in egg production were obtained with three experiments employing diammonium citrate, ammonium sulfate, and diammonium phosphate as non-protein nitrogen sources. Non-essential nitrogen consumptions of hens fed diets which responded to non-protein nitrogen supplementation were below 1.4 gm./day. The non-protein nitrogen additions increased the non-essential nitrogen intakes to 1.4–1.9 gm./day. The results of these experiments suggest that the conversion of essential amino nitrogen to non-essential nitrogen by hens fed the diets in these studies was relatively inefficient and that the non-protein nitrogen additions exerted a “sparing” effect on essential amino nitrogen. These data suggest that the minimum amount of essential amino nitrogen required for egg production levels of 70–75% was in the order of 1.1 gm./day with the amino acid balances employed. The non-essential nitrogen requirement appears to be 1.4–1.9 gm./day, of which 0.4 gm. could be furnished by non-protein nitrogen sources.