title: Effect of activated protein C in second intention healing of equine distal limb wounds: a preliminary study.
abstract: OBJECTIVE
  To investigate the effect of activated protein C (APC) on second intention healing of distal limb wounds in horses.
  
  
  METHODS
  In this experimental study of eight Standardbred geldings, six full-thickness skin wounds (2 × 1.5 cm) were created on one metacarpus (biopsy limb) and five similar wounds were created on the contralateral metacarpus (photographed limb). Three wounds on the biopsy limb were treated topically with 190 µg APC on days 1, 3, 6 and 9, while the remaining three wounds were untreated (control). One treated and one control wound were biopsied on days 4, 7 and 11 for histopathology. Wounds on the photographed limb were treated with either 66% Manuka honey gel, a commercial antibiotic ointment (bacitracin-neomycin-polymixin B ointment; BNP) or petrolatum daily throughout healing, treated on days 1,3,6 and 9 with 190 µg APC or left untreated. These wounds were digitally photographed and the wound area measured on day 1, then weekly until day 49. Overall time to healing was recorded.
  
  
  RESULTS
  There was no effect of APC on wound size, the rate of healing or the overall time to heal. However, compared with control wounds, histological scoring demonstrated enhanced epithelialisation (day 4) and angiogenesis (day 11). Wound healing variables for wounds treated with APC, Manuka honey gel and control wounds were not different and the variables for wounds treated with BNP and petrolatum demonstrated delayed healing.
  
  
  CONCLUSIONS
  The improvements in histological scores in APC-treated wounds suggest further study into the effect of APC on second intention wound healing in horses is warranted.
authors.affiliation: Research and Clinical Trials Unit, University Veterinary Teaching Hospital Camden, University of Sydney, 410 Werombi Road, Camden, New South Wales, 2570, Australia.
authors.forename: A S
authors.initials: AS
authors.lastname: Bischofberger
authors.affiliation: Research and Clinical Trials Unit, University Veterinary Teaching Hospital Camden, University of Sydney, 410 Werombi Road, Camden, New South Wales, 2570, Australia.
authors.forename: A S
authors.initials: AS
authors.lastname: Tsang
authors.affiliation: Research and Clinical Trials Unit, University Veterinary Teaching Hospital Camden, University of Sydney, 410 Werombi Road, Camden, New South Wales, 2570, Australia.
authors.forename: N
authors.initials: N
authors.lastname: Horadagoda
authors.affiliation: Research and Clinical Trials Unit, University Veterinary Teaching Hospital Camden, University of Sydney, 410 Werombi Road, Camden, New South Wales, 2570, Australia.
authors.forename: C M
authors.initials: CM
authors.lastname: Dart
authors.affiliation: Ausvet Animal Health Services, Toowoomba, QLD, Australia.
authors.forename: N R
authors.initials: NR
authors.lastname: Perkins
authors.affiliation: Research and Clinical Trials Unit, University Veterinary Teaching Hospital Camden, University of Sydney, 410 Werombi Road, Camden, New South Wales, 2570, Australia.
authors.forename: L B
authors.initials: LB
authors.lastname: Jeffcott
authors.affiliation: Sutton Arthritis Research Laboratories, Kolling Institute of Medical Research, University of Sydney at Royal North Shore Hospital, NSW, Australia.
authors.forename: C J
authors.identifier: http://orcid.org/0000-0001-5329-1292
authors.initials: CJ
authors.lastname: Jackson
authors.affiliation: Research and Clinical Trials Unit, University Veterinary Teaching Hospital Camden, University of Sydney, 410 Werombi Road, Camden, New South Wales, 2570, Australia. andrew.dart@sydney.edu.au.
authors.forename: A J
authors.initials: AJ
authors.lastname: Dart
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000890:Anti-Infective Agents / Q000494:pharmacology*; D001414:Bacitracin / Q000494:pharmacology; D004338:Drug Combinations; D005782:Gels; D006722:Honey; D006736:Horses; D035002:Lower Extremity / Q000293:injuries / Q000503:physiopathology; D008297:Male; D009355:Neomycin / Q000494:pharmacology; D010781:Photography; D011112:Polymyxin B / Q000494:pharmacology; D011486:Protein C / Q000494:pharmacology*; D011897:Random Allocation; D011994:Recombinant Proteins / Q000494:pharmacology; D012867:Skin / Q000187:drug effects* / Q000293:injuries; D014945:Wound Healing / Q000187:drug effects* / Q000502:physiology
chemical_list: D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D004338:Drug Combinations; D005782:Gels; D011486:Protein C; D011994:Recombinant Proteins; D001414:Bacitracin; C001816:bacitracin zinc, neomycin sulfate, polymyxin B, drug combination; D009355:Neomycin; D011112:Polymyxin B; C421124:drotrecogin alfa activated
keywords: Manuka honey gel; activated protein C; bacitracin; horses; neomycin; petrolatum; polymixin B ointment; wound healing