DIET EFFECT ON ACTIVITY PRODUCT RATIOS OF URIC-ACID, SODIUM URATE, AND AMMONIUM URATE IN URINE FORMED BY HEALTHY BEAGLES

Urine activity product ratios of uric acid, sodium urate, and ammonium urate and urinary excretion of metabolites were determined in 24-hour samples produced by 6 healthy Beagles during periods of consumption o f a low-protein, casein-based diet (diet A) and a high-protein, meat-b ased diet (diet B). Comparison of effects of diet A with those of diet B revealed: significantly lower activity product ratios of uric acid (P = 0.025), sodium urate (P = 0.045), and ammonium urate (P = 0.0045) ; significantly lower 24-hour urinary excretion of uric acid (P = 0.00 2), ammonia (P = 0.0002), sodium (P = 0.01), calcium (P = 0.005), phos phorus (P = 0.0003), magnesium (P = 0.01), and oxalic acid (P = 0.004) ; significantly (P = 0.0001) higher 24-hour urine pH; and significantl y (P = 0.01) lower endogenous creatinine clearance. These results sugg est that consumption of diet A minimizes changes in urine that predisp ose dogs to uric acid, sodium urate, and ammonium urate urolithiasis.