There are two aspects that are important to consider in biting and mouthing type behaviors in dogs. The first component is the age of the dog or puppy, and the second is the reason that the dog or puppy is engaging in these behaviors in the first place. There are several normal reasons why a dog or puppy might chew or bite, and then there are some abnormal or serious issues that may be causing this behavior. One of the most serious of the health related issues for dogs biting and mouthing includes a condition known as Pica. Pica is defined as the eating of inedible objects and may be related to nutritional deficiencies, bad habits, boredom or attention seeking behaviors. It is important to take your adult dog to the vet if you notice pica type behaviors and have a full check-up completed to see if there are any health related conditions that may need treatment.
Puppies will normally go through times where they engage in what is known as mouthing. Mouthing is really the puppy's only way to explore their environment when they are small, especially before their eyes are open and their sense of hearing is fully developed, however it often still continues afterwards. Puppies that mouth are only doing what is natural for them. If you watch puppies playing, especially when they are under twelve weeks of age, you will notice that they even bite or mouth other dogs, their brothers and sisters and even their mother. During this time puppies learn what is called bite inhibition. This is when the puppy bites or mouths too hard and it hurts the other puppy or the mother dog. The mother or puppy will then give a shrill yelp that lets the puppy know that he or she has gone too far and bitten down too hard. The result of this interaction is the hurt or injured puppy leaves the other puppy alone, reinforcing the fact that if a puppy bites he or she will have not attention or anyone to play with.
When puppies first interact with people they treat them just like other puppies. Fingers are especially interesting to puppies are usually the first thing that the puppy investigates when a human reaches down to provide a pat or picks the puppy up. If you notice many people will allow puppies to chew on their fingers, which can reinforce a bad habit, even if the puppy is not biting too hard. It is a good idea to replace your fingers with an appropriate chew toy and prevent the puppy from biting in the first place. If a puppy does mouth and bites down to hard, respond just like he or she is used to. Give high pitched "Ouch, no bite", then ignore the puppy for a minute or two. This is all that most puppies need to realize that they can't bite people. Some puppies will be less likely to stop mouthing, typically these are the more dominant or aggressive puppies that have used biting to show their dominance in the litter. These puppies may need more direct training including immediately giving them a chew toy and then rewarding them for chewing that rather than on your hand. The will also need longer ignoring time before they respond to the positive training. Hitting, flicking or punishing the puppy for biting or mouthing is not an effective way to prevent the behavior as it is likely to be seen as a dominance issue for the puppy and may even permanently prevent a strong sense of trust forming between the puppy and the owner.
Biting, mouthing and chewing is also typically seen when puppies are losing their adult teeth and getting their puppy teeth. This is typical, just like when a baby is teething. There are special puppy teething rings that can be frozen that will really help at this time.
Biting behavior in adult dogs can be pica related, nutritionally motivated, or simply a bad behavior or aggressive behavior that the dog has been allowed to develop over time. Stopping a dog from biting should be a priority for an owner as most areas now have zero tolerance laws that require dogs that bite to be destroyed. Training a biting dog to stop may involve some very direct teaching methods. One of the best methods to prevent biting is to provide socialization opportunities to the dog in the form of an obedience class. It is important to notify the trainer that the dog has biting issues so he or she can be prepared to work with you to help socialize the dog and teach appropriate replacement behaviors for the biting. Most dogs bite because they are frightened, nervous or scared, as well as because they are overly aggressive. All of these issues can be addressed through socialization and obedience training.
The dog will often bite or treat a human like a companion dog if there is no sense of hierarchy or place within the pack for the dog. If the dog thinks he or she is the dominant member of the family they will use biting to maintain their place as the leader. Training your dog in all areas and being the person in charge in a positive, rewarding way will help your dog understand that he or she is not in control, you are.
For herding breeds nipping at heels is a natural behavior for herding livestock, but not for interacting with people. If the "Ouch, no bite" doesn't work, you may have to carry a small spray bottle filled with clean, clear water. When the dog approaches in its herding stance try to distract it with a command such as come or sit. If it responds, give a reward and typically this will end the "attack". If the dog keeps approaching, use the "No bite" command and keep walking. If the dog approaches to nip at your heels say "No Bite" and spray a jet of water from the bottle at the end of the dog's nose. As soon as he or she stops, give a sit command, then reward for good behavior. Never engage a nipping or biting dog in any type of game that may encourage this behavior.
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