Effects of dietary potassium citrate supplementation on urine pH and urinary relative supersaturation of calcium oxalate and struvite in healthy dogs.
OBJECTIVE
To assess the effect of dietary potassium citrate supplementation on the urinary pH, relative supersaturation of calcium oxalate and struvite (defined as the activity product/solubility product of the substance), and concentrations of magnesium, ammonium, phosphate, citrate, calcium, and oxalate in dogs.


METHODS
12 healthy adult dogs.


METHODS
Canned dog food was fed to dogs for 37 days. Dogs were randomly allocated to 3 groups and fed test diets for a period of 8 days. Study periods were separated by 6-day intervals. During each study period the dogs were fed either standard diet solus (control) or standard diet plus 1 of 2 types of potassium citrate supplements (150 mg potassium citrate/kg of body weight/d) twice daily. Urinary pH, volume and specific gravity, relative supersaturation of calcium oxalate and struvite, and concentrations of magnesium, ammonium, phosphate, calcium, oxalate, and citrate were assessed for each treatment.


RESULTS
Mean urine pH was not significantly affected by dietary potassium citrate supplementation, although urine pH did increase by 0.2 pH units with supplementation. Diets containing potassium citrate maintained a higher urine pH for a longer part of the day than control diet. Three Miniature Schnauzers had a significantly lower urinary relative calcium oxalate supersaturation when fed a diet supplemented with potassium citrate, compared with control diet.


CONCLUSIONS
Dietary potassium citrate supplementation has limited effects on urinary variables in most healthy dogs, although supplementation results in maintenance of a higher urine pH later in the day. Consequently, if supplementation is introduced, dogs should be fed twice daily and potassium citrate should be given with both meals or with the evening meal only.
Stevenson
A E
AE
WALTHAM Centre for Pet Nutrition, Melton Mowbray, Leicestershire, UK.
Wrigglesworth
D J
DJ
Smith
B H
BH
Markwell
P J
PJ
D000818:Animals; D001835:Body Weight; D002129:Calcium Oxalate / Q000652:urine*; D002940:Circadian Rhythm; D004285:Dogs / Q000652:urine*; D002149:Energy Intake; D005260:Female; D006863:Hydrogen-Ion Concentration; D017616:Magnesium Compounds / Q000652:urine*; D008297:Male; D010710:Phosphates / Q000652:urine*; D019357:Potassium Citrate / Q000494:pharmacology*; D017419:Potassium, Dietary / Q000494:pharmacology*; D000069877:Struvite; D014556:Urine
D017616:Magnesium Compounds; D010710:Phosphates; D017419:Potassium, Dietary; D002129:Calcium Oxalate; D000069877:Struvite; D019357:Potassium Citrate