The saying “to lick one’s wounds” is a metaphor that is synonymous with retreating and recovering from an harm, and the conduct is noticed in some pets and different animals. Dogs do it (opens in new tab); mice do it (opens in new tab); even ants do it. All types of critters apply their saliva to scratches and scrapes. But why do these animals lick their wounds?
The reply lies largely within the self-soothing actions of licking and the therapeutic properties of spit. Wound licking is an instinctual response, honed by pure choice, that will assuage irritation and ache and may even assist accidents get better sooner, in accordance with Dr. Benjamin Hart, a retired veterinarian and professor emeritus on the University of California, Davis. But in canines and different pets, the intuition can simply grow to be counterproductive, particularly when there are much better wound therapies accessible.
For animals “without thumbs or medication,” licking is “the best they probably have,” stated Dr. Kristi Flynn, a veterinarian and animal conduct skilled on the University of Minnesota. Licking can take away particles, comparable to dust or bits of stray pores and skin, from a wound, whereas serving to to alleviate soreness, Flynn stated. It’s just like how an individual may rub their foot after stubbing a toe or clutch their arm after leaning towards a scorching range. “When [animals] feel pain, it’s a natural inclination to try to soothe an area,” Flynn informed Live Science.
Hart agreed. “Licking wounds is an instinct in dogs that goes way back to the wolf ancestor,” Hart informed Live Science. “They’ve got a wound; they’ve got an instinct to lick it: keep it clean and wash off the dirt and the grime.” And past the speedy try to appease, the analysis of Hart and others has proven that some animals’ saliva (together with people (opens in new tab)) has antibacterial and tissue and nerve growth-promoting properties that pace therapeutic (opens in new tab).
For instance, canine saliva is efficient at killing Streptococcus canis, a type of strep that primarily infects animals, and E. coli (opens in new tab) micro organism, in accordance with a 1990 research co-written by Hart and printed within the journal Physiology & Behavior (opens in new tab). Another 2018 research evaluating canine and human saliva from the journal PLOS One (opens in new tab) discovered a number of immune and cell development proteins particular to canine saliva. Meanwhile, rodent spit comprises compounds that promote pores and skin development and wound closure, in accordance with a 1979 research within the journal Nature (opens in new tab) and a 1991 research within the journal Experimental Gerontology (opens in new tab). Similar development components are additionally present in small portions in human saliva, in accordance with a 2019 research within the Archives of Oral Biology (opens in new tab).
However, within the age of contemporary drugs for each pets and other people, wound licking may cause extra hurt than good, which is why cats and canines usually come house from the vet carrying a plastic collar. Licking a surgical wound website can injury or pull out sutures, and this “makes a very small lesion into a big, big mess,” Flynn stated. Dogs are particularly susceptible to extreme licking, which may forestall accidents from therapeutic. “They make a mountain out of a molehill and just don’t have the judgment to stop,” Flynn stated.
Licking wounds may also improve the chance of an infection by introducing mouth micro organism to the injured website, Flynn added. Though saliva has some antibacterial properties, it isn’t a common germ killer. For occasion, Hart’s 1990 analysis revealed that canine spit did not kill Staphylococcus, a genus of micro organism that trigger staph infections and are generally present in wounds.
So, if wound licking is just not significantly useful, why did it evolve and persist over many generations?
“Things that evolve aren’t 100% correct,” Hart stated. “They have to be useful 75% of the time or 50% of the time, and they’ll still be maintained by natural selection because it’s better than nothing.”
But trendy science and drugs normally advance sooner than evolution. Wound licking is an effective resolution for wild animals with no different options. For house owners of pet cats and canines, nevertheless, it is higher to hearken to a veterinarian’s recommendation.
Originally printed on Live Science.