Variation in the potassium needs of chickens selected genetically for variation in blood uric acid concentrations.

Two strains of sex-linked dwarf chickens that have been selected genetically for divergence in plasma uric acid concentrations were found to differ in their requirements for potassium. The rates of growth of chicks from both strains were similar when nutritionally adequate levels of potassium were provided. However, the growth of chicks having normal plasma uric acid concentrations was significantly poorer than that of hyperuricemic chicks when the chicks received potassium-deficient diets, and the retention of dietary potassium was less in the former group. There were no consistent strain differences in response to sodium deficiency. Because the two strains previously were found to differ in the renal tubular transport of uric acid, the strain difference in potassium requirement may reflect an association of potassium with uric acid excretion.