Comparison of two methods for presurgical disinfection of the equine hoof.
OBJECTIVE
To determine for equine hooves the normal resident aerobic bacterial population and the efficacy of 2 methods of disinfection. Study Design-Measurement of total bacterial, gram-positive bacterial, and gram-negative bacterial surface populations from the frog, sole, and hoof wall after each step of 2 different preoperative surgical disinfection techniques.


METHODS
Six adult horses.


METHODS
Hoof wall, sole, and frog samples were collected for quantitative bacteriology before, during, and after 2 multistep antiseptic preparation techniques: Method A-6-minute scrub with povidone-iodine soap, followed by 24-hour submersion in povidone-iodine solution-soaked cotton; and Method B-initial removal of superficial layer of hoof capsule before completing Method A disinfection procedures.


RESULTS
Removal of the superficial hoof layer, application of the povidone iodine scrub, and completion of the povidone-iodine soak all significantly (P < .0008) decreased total bacterial numbers. Method B had significantly lower bacterial counts than method A at each consecutive step. Final total bacterial counts remained greater than 10(5) bacteria per gram of tissue regardless of preparation method.


CONCLUSIONS
The hoof surface hosts a broad spectrum of aerobic gram-positive and -negative bacteria, many of which are potential pathogens. Bacterial numbers can be significantly reduced by removal of the superficial hoof surface, by application of a povidone-iodine scrub, and by use of a 24-hour povidone-iodine soak. However, bacterial populations >10(5) g per tissue persist after these disinfection procedures.


CONCLUSIONS
Regardless of the preparation methods used in this study, bacterial populations capable of inducing wound infection remain on the hoof capsule.
Hennig
G E
GE
Department of Surgery, Tufts University School of Veterinary Medicine, North Grafton, MA, USA.
Kraus
B H
BH
Fister
R
R
King
V L
VL
Steckel
R R
RR
Kirker-Head
C A
CA
D000818:Animals; D000891:Anti-Infective Agents, Local / Q000008:administration & dosage / Q000494:pharmacology*; D015169:Colony Count, Microbial; D004203:Disinfection / Q000379:methods*; D006090:Gram-Negative Bacteria / Q000187:drug effects / Q000302:isolation & purification; D006094:Gram-Positive Bacteria / Q000187:drug effects / Q000302:isolation & purification; D006724:Hoof and Claw / Q000382:microbiology*; D006736:Horses / Q000382:microbiology* / Q000601:surgery*; D011206:Povidone-Iodine / Q000008:administration & dosage / Q000494:pharmacology*; D011300:Preoperative Care / Q000662:veterinary*
D000891:Anti-Infective Agents, Local; D011206:Povidone-Iodine