RELIABILITY OF CARNITINE CONCENTRATIONS MEASURED IN SINGLE POSTPRANDIAL URINE SAMPLES FROM DOGS

Objective-To evaluate the reliability of urine carnitine concentration s measured in single postprandial samples, compared with carnitine con centrations measured in 24-hour urine samples. Animals-19 healthy Beag les. Procedure-Alter emptying the urinary bladder by catheterization, dogs were fed a canned canine maintenance diet. Approximately 8 hours later, urine, plasma, and serum samples were obtained for determinatio n oi urinary carnitine fractional excretion and urine carnitine-to-cre atinine concentration ratio. Results were compared with 24-hour urinar y carnitine excretion rate. Results-Fractional excretion of carnitine and urine carnitine-to-creatinine ratios correlated poorly with 24-hou r urinary carnitine excretion. Conclusion-Determination of 24-hour uri nary carnitine excretion is recommended to measure urine carnitine con centrations in dogs.