The SF SPCA's Dr. Jeannine Berger, DVM, DACVB is a board certified veterinary behaviorist who counsels guardians whose pets' issues are beyond the scope of training. Think of her as a pet shrink…at your service.
Q: Why does my dog want to kiss me on the mouth? It happens always, not just after I eat something scrumptious. I deter him all the time, but anytime he has the chance, he goes for it!
A: This behavior has most likely an evolutionary reason. Licking in dogs is a form of communication for different reasons.
When puppies are born, their mother will lick her puppies to clean them and to stimulate their little digestive systems. Sometimes, mamas never stop performing these nurturing rituals for their kids. I have a Chihuahua who cleans her 4 year old son's ears and face every day. This nurturing behavior is referred to as epimiletic behavior.
This is a mutually bonding exercise. The puppy will respond by licking the mother's face, wag his tail and follow his mom around. This is care-seeking behavior. Licking the mom's mouth also familiarizes the little one with the smells and tastes of the solid food he will soon be eating.
Puppies also lick the mouth of adult dogs and people for submissive reasons, as if to say, “I am just a puppy." It's a form of submissive greeting behavior.
In some cases however, a dog might lick as a displacement behavior; for example, some people put their faces directly in a dog's face and the dog is uncomfortable with this direct close approach and is actually a bit frightened. Instead of growling or snapping, there are dogs that show their discomfort of such a “human in the face approach" by licking, the ears might go back and the tail is down. Then the human should stop and make the dog more comfortable by not being so close, otherwise, it could escalate to a growl or snap to keep the person away.
Unless you are noticing body language that corresponds to displacement behavior, your dog is giving you submissive kisses. You can easily stop that behavior – not by pushing him down or yelling at him – because I am sure you want your dog to greet you happily, but by teaching him how you would like to be greeted. Have him sit for all greetings and ignore all licking or walk away from him. If you get up and leave when he licks you, (the opposite of what your dog really wants), he will stop the licking over time. When you pet your dog and he starts licking, stop the petting immediately. Some dogs that have strong oral needs are easily trained to pick up a ball or a toy for greeting.
My chihuahuas want to kiss all the time, so I taught them “Kiss" as a commands and reward for it – if I don't give the command, there will be no reward, and therefore no reason to kiss.
Good Luck and Go Giants!