Sadie, my 8-year-old golden retriever, used to be the best tennis-ball-and-Frisbee-catching dog in the neighborhood; that is, until she sustained a typical "jock" injury—a ruptured cruciate ligament—which necessitated orthopedic surgery and a suture line from hip to ankle. To protect the wound, the veterinarians put on a large cone, euphemistically called an Elizabethan collar, over her head to prevent her from licking the wound. This torture led me to question what is known about wound licking and wound healing. Certainly there must be a reason that animals naturally lick their wounds, right?
Right. Hutson et al1 created wounds in mice and observed that wounds accessible to licking healed faster than inaccessible (dorsal) wounds in individually caged mice. They also observed that removal of the salivary glands at the time of wounding delayed wound closure in individually caged animals, compared with sham-operated controls, but that this delay did not occur
Sherertz EF. Why Sadie Licks Her Wounds. Arch Dermatol. 1988;124(10):1499-1500. doi:10.1001/archderm.1988.01670100011003