If a grown dog is chewing and it’s a new behavior, you need to look at the dog’s day. Ask yourself these questions:
• Is my dog getting enough exercise during the day?
• Is my dog mentally stimulated during the day while I am at work?
• Is my dog chewing only when I am away from home?
A “yes” answer to any of these questions indicates that your dog may be chewing because he is bored. Before leaving the house, take your dog for a long walk and do your training to stimulate his mind and body. Provide him with chew toys to keep him busy while you are gone. Chew toys that can be stuffed with an edible filling (such as those made by Kong or the Tire Biter line of toys) can be especially helpful. You can fill them with commercially prepared fillings, or make your own with peanut butter, spray cheese, or any similar filling your dog loves. You can even mix in chopped hot dogs or cold cuts. Try freezing the filled toys to add to the chew time.
When you see your dog chewing something he shouldn’t, take it out of his mouth and replace it with an appropriate chew toy, then praise him. Your dog wants to please you, so the more positive training you provide, the faster he will learn.