The primary catabolic end product of protein, non-protein nitrogen and purines depends upon a reptile’s natural environment. Terrestrial reptiles excrete uric acid as the primary nitrogenous waste product, i.e. they are uricotelic. Uric acid is synthesised in the liver and excreted by renal tubular secretion. The blood level is therefore largely independent of urine flow rate (and is therefore not a sensitive indicator of dehydration in reptiles or birds). Both animal and environmental factors influence uric acid levels. The normal blood uric acid value for most reptiles is 0 to 600 µmol/l. | The primary catabolic end product of protein, non-protein nitrogen and purines depends upon a reptile’s natural environment. Terrestrial reptiles excrete uric acid as the primary nitrogenous waste product, i.e. they are uricotelic. Uric acid is synthesised in the liver and excreted by renal tubular secretion. The blood level is therefore largely independent of urine flow rate (and is therefore not a sensitive indicator of dehydration in reptiles or birds). Both animal and environmental factors influence uric acid levels. The normal blood uric acid value for most reptiles is 0 to 600 µmol/l. |