The effect of boric acid on bacterial culture of canine and feline urine

J Small Anim Pract. 2011 Oct;52(10):510-4. doi: 10.1111/j.1748-5827.2011.01102.x.


Objective: To identify the optimal method of submission of canine and feline urine for bacterial culture.

Methods: Cystocentesis samples from 250 animals (200 dogs, 50 cats) suspected of having urinary tract infections were collected. The reference aliquot, without preservative, was processed on site within 2 hours. Two further aliquots (one without preservative, one with boric acid) were stored at room temperature for up to 7 hours and then posted by guaranteed next day delivery to a commercial laboratory for analysis.

Results: Forty-seven of the samples were positive on culture in the reference test. There was no significant difference between reference test results and those of samples posted without preservative (P=0·39), but samples posted in boric acid were significantly less likely to give a positive result (P=0·01). Samples posted without preservative had a sensitivity of 82% and a specificity of 98%; for boric acid, sensitivity was 73% and specificity 99%.

Clinical significance: Postal urine samples should be submitted to the laboratory in a plain sterile tube.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bacteria / drug effects*
  • Bacteria / growth & development
  • Bacteriuria / diagnosis
  • Bacteriuria / veterinary*
  • Boric Acids / pharmacology*
  • Cat Diseases / diagnosis*
  • Cat Diseases / urine
  • Cats
  • Colony Count, Microbial
  • Dog Diseases / diagnosis*
  • Dogs
  • Female
  • Male
  • Sensitivity and Specificity
  • Specimen Handling / methods
  • Specimen Handling / veterinary*
  • Urine / microbiology*


  • Boric Acids
  • boric acid