What is the protein equivalent of urea?

The feed-grade urea most commonly available today contains 45 percent nitrogen. Therefore, 100 pounds of 45-percent urea contains 45 pounds of nitrogen. Because natural protein is about 16 percent nitrogen, there is 1 pound of nitrogen in each 6.25 pounds of protein (100 lb ÷ 16% = 6.25 lb). Thus, the “equivalent” protein in 100 pounds of 45-percent nitrogen urea is 281 pounds of protein equivalent.