VLD 411: Veterinary Clinical Biochemistry and Laboratory Diagnosis - I (0+1)

REACTION OF THE URINE

• It varies in different species and individuals, depending upon the diet and metabolism. In herbivores, the reaction is alkaline, where as in carnivores and omnivores, it is acidic.
  • Horse - alkaline (pH 8)
  • Cattle - alkaline (pH 7.4 to 8.4)
  • Sheep - alkaline
  • Pig - acidic or alkaline
  • Dog - acidic (pH 6 to 7)
  • Cat - acidic (pH 6 to 7)
  • Man - usually acidic (pH 4.8 to 7.5)
• Reaction is detected using a litmus paper. Acid urine turns blue litmus red. Alkaline urine turns red litmus blue.

Interpretation

• Acidic urine
  • Normal in carnivorous animals
  • Nursing calves and foals that are on milk
  • Diet with an excess of protein
  • Starvation – catabolism of body proteins
  • Fever
  • Acidosis – both metabolic and respiratory
    • Diabetes mellitus
    • Uraemia
  • Prolonged muscular activity
  • Administration of acid salts
    • Sodium acid phosphate
    • Ammonium chloride
    • Sodium chloride
    • Calcium chloride
• Alkaline urine
  • Normal in herbivorous animals
  • Vegetable diet
  • Cystitis
  • Urine retention – decomposition of urea to ammonia
  • Rapid absorption of transudates
  • Alkalosis – both metabolic and respiratory
  • Alkaline therapy
    • Sodium bicarbonate
    • Sodium and potassium citrate or acetate
    • Sodium lactate
    • Potassium nitrate
  • Urine becomes alkaline when the sample is kept at room temperature because of ammonia formation as a result of decomposition of urea.