Camels were given different diets with varying protein levels, and their urea metabolism was studied using a special type of urea. As the camels ate more protein, their urea levels in the blood and urine increased. The camels broke down about 86% of urea on the low-protein diet, 74% on the medium-protein diet, and 47% on the high-protein diet. The more protein the camels ate, the more urea they produced and excreted. The researchers found that the amount of urea in the blood and urine was related to how much urea the camels were making and breaking down.