All dogs are capable of biting. Aggression is normal canine behavior. What provokes a dog to bite depends on his genetic makeup and what he's learned will work for him. Aggression is not curable. However, with behavior modification training, and sometimes with medication, we may be able to raise the dog's bite threshold so that he can handle more stress in his life without getting to the point of exploding.
You can think of your aggressive dog the way you would view an alcoholic. An alcoholic is always said to be in recovery. Once you begin to work with your dog, you should consider him also to be "in recovery" for the rest of his life.
If you decide to embark on helping your dog become a safer, happier companion pet, you must recognize that this will take time, patience and consistency. You must also recognize that if medication is indicated, this could be costly. Anytime we interact with an aggressive dog there are risks involved. If you have young children in your home, are you willing to put those children at risk? What would happen if one of your children's friends came to visit and your dog bit that child? You could be sued. Will you be able to teach your children how to properly interact with your dog so as not to provoke a biting incident? These are all things to consider if you want to make the commitment to rehabilitate your dog.
In many instances, while you work on modifying your dog's behavior, everyone who lives with your dog will also have to modify their behavior in order to prevent your dog from becoming reactive toward them, or to other people your dog will encounter in his life. While it may be heartbreaking to make this decision, you may have to consider euthanasia as a viable alternative. If you attempt treatment and it proves unsuccessful, euthanasia may be your only choice.
In order to teach your dog more appropriate behaviors to use in place of aggressive behaviors, you must prevent him from ever showing aggression again. Each time a dog practices aggression, he learns this is a very powerful strategy to use to avoid something negative or to get something he wants. To help your dog avoid showing aggression, you must avoid putting your dog into any situation that would trigger that response. Since stress is a huge factor in creating aggressive behavior, recognize situations that may cause your dog to feel stressed. Author and trainer Turid Rugaas has written a book called, On Talking Terms with Dogs: Calming Signals, published by Legacy By Mail, Inc, 1997. The following is a list of situations that stress dogs (Rugaas, p. 25):
Being threatened directly by us or other dogs
Being exposed to violence, anger or aggression
Jerking his leash, forcing him down, yanking on his collar to move him
Making unrealistic demands on him in training and in life Over-exercising young dogs
Not enough exercise and activity
Hunger and thirst
Not having access to outside potty area when necessary Temperature extremes
Pain and illness
Being alone and feeling isolated
Sudden and frightening situations
Overstimulation from playing with balls or other dogs
Always being disturbed and not getting enough down time
Any sudden changes in his routine or his life
The following is a list of indicators your dog might give when he is feeling stressed (Rugaas, p. 26):
Over-reacting to something happening; i.e., doorbell, an approaching dog, etc.
Scratching himself Biting himself
Chewing on inedible items, such as furniture, shoes, etc. Barking, howling or whining
Bouts of Diarrhea
Dog smells bad, both mouth and bod
Tenseness of muscles
Sudden onset of dandruff and shedding
Change of eye color
Dog licks himself
Raised hackles (piloerection)
Lack of concentration
Loss of appetite
Fixating on certain stimuli; i.e, lights, flies, crackling firewood
Appearing to be nervous
Use of displacement behaviors
You will benefit by being able to identify those calming signals dogs give when they are experiencing stress (Rugaas, pp. 5-14):
Turning of the head: Dog swiftly turns his head to the side and back or the head can be held to one side for awhile.
Eyes shift from side to side while the dog's head remains still.
Turning away: dog turns to the side or back
Freezing in place
Walking slowly and using very slow movements
Quick downs: dog lies down with his belly to the ground Yawning
Sniffing: quick movement with head down to the ground Splitting up: dog goes between people or other dogs
Finally, you will recognize the following signs of aggression as preludes to a possible biting incident (The Canine Aggression Workbook, by James O'Heare, published by Gentle Solutions, 2001, p. 13):
Snarling (lips raised and teeth bared)
Staring Piloerection (raised hackles)
Stiff, high tail wag
Freezing in place
Dog closes his mouth prior to biting