Reference limits for urinary fractional excretion of electrolytes in adult non-racing Greyhound dogs

Objective To determine reference limits for urinary fractional excretion of electrolytes in Greyhound dogs. Methods Urinary fractional excretion was calculated using a spot clearance method preceded by a 16 to 20 hour fast in 48 Greyhound dogs. Raw data analysed using the bootstrap estimate was used to calculate the reference limits. Results The observed range for urinary fractional excretion in Greyhound dogs was 0.0 to 0.77% for sodium, 0.9 to 14.7% for potassium, 0 to 0.66% for chloride, 0.03 to 0.22% for calcium and 0.4 to 20.1% for phosphate. Expressed as percentages, the suggested reference limits for fractional excretion in Greyhound dogs are as follows: sodium: 0.72, potassium <= 12.2, chloride <= 0.55, calcium <= 0.13 and phosphate <= 16.5. Clinical significance Veterinary practitioners may use these reference limits for urinary electrolyte fractional excretion when investigating renal tubular disease in Greyhound dogs.