title: Residual antibacterial activity of canine hair treated with topical antimicrobial sprays against Staphylococcus pseudintermedius in vitro.
abstract: BACKGROUND
  Topical antimicrobial therapy is increasingly important in the treatment of canine pyoderma as the incidence of multidrug resistance has risen. However, little information is reported on the persistence of activity of topical antimicrobial products.
  
  
  OBJECTIVE
  To determine the residual antibacterial activity of canine hairs treated with antimicrobial sprays.
  
  
  METHODS
  Twelve privately owned dogs with no history of dermatological disease.
  
  
  METHODS
  Dogs were treated once with four different spray products [(A) 1% chlorhexidine digluconate, (B) 2% miconazole nitrate, 2% chlorhexidine gluconate, tromethamine USP/disodium EDTA (TrizEDTA), (C) 3% chlorhexidine gluconate, phytosphingosine salicyloyl and (D) 4% chlorhexidine gluconate, TrizEDTA] in separate 5 × 5 cm sections on the trunk. Hairs were collected via shaving before, one hour after and 2, 4, 7 and 10 days after treatment. Hairs were incubated on agar plates streaked with Staphylococcus pseudintermedius for 24 h and the bacterial growth inhibition zone around the hairs was measured.
  
  
  RESULTS
  There were significant overall treatment and day (P < 0.0001) differences in inhibition zones. The largest zones of inhibition were from hairs treated with spray B, followed by sprays D, C and A, respectively. All sprays demonstrated residual antimicrobial activity for the ten days evaluated.
  
  
  CONCLUSIONS
  Results suggest that the efficacy of an antimicrobial spray is dependent on both the concentration and combination of active ingredients. Several ingredient profiles appear to effectively inhibit S. pseudintermedius growth for at least 10 days, which may be beneficial in the treatment of canine pyoderma.
authors.affiliation: Animal Dermatology Clinic, 4834 Lincoln Boulevard, Marina del Rey, CA, 90293, USA.
authors.forename: Mollie L
authors.initials: ML
authors.lastname: Mesman
authors.affiliation: Animal Dermatology Clinic, 4834 Lincoln Boulevard, Marina del Rey, CA, 90293, USA.
authors.forename: Allison L
authors.initials: AL
authors.lastname: Kirby
authors.affiliation: Animal Dermatology Clinic, 2965 Edinger Avenue, Tustin, CA, 92780, USA.
authors.forename: Wayne S
authors.initials: WS
authors.lastname: Rosenkrantz
authors.affiliation: Animal Dermatology Clinic, 5610 Kearny Mesa Road, San Diego, CA, 92111, USA.
authors.forename: Craig E
authors.initials: CE
authors.lastname: Griffin
mesh_terms: D000287:Administration, Topical; D000336:Aerosols; D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000494:pharmacology*; D018592:Cross-Over Studies; D004285:Dogs; D006197:Hair / Q000737:chemistry*; D013210:Staphylococcus / Q000145:classification / Q000187:drug effects*
chemical_list: D000336:Aerosols; D000900:Anti-Bacterial Agents