There are a lot of misconceptions about playing tug with your dog. In my experience, (and lots of other trainers I respect) as long as you teach your dog some ground rules, tug is a great way to condition your dog to have a soft mouth as well as providing your dog exercise.
The rules of tug are as follows:
- Your dog should never take the tug toy out of your hand without you first saying, "take it". This will prevent your dog from grabbing items out of your hand that are not intended for tug.
- Your dog should not put teeth on your skin. Even if you feel the slightest bit of teeth on your skin, say, "Ouch!" and remove the toy for 3-5 seconds and then start again. It is important to do this even if your dog doesn't hurt you. The key is to make sure your dog practices being gentle.
- Your dog should drop on cue. Keep in mind that is more difficult to teach your dog to drop if there is a lot of tension on the tug toy because there is more pressure on his teeth. You might try letting go of the object before you ask for drop.
- If your dog seems to get too excited or seems aggressive, give him a break and walk away when he reaches this level. If you are consistent, he can learn to moderate his level of excitement.
- Vocalization or growling doesn't always mean aggression. Some dogs are just vocal when they play tug. As long as your dog is exercising self-control, is not touching your skin with his teeth, and drops on cue, the vocalization is ok.
- If your dog doesn't know how to drop, say, "drop" one time, pause for a moment and then put a treat under his nose. As soon as he opens his mouth, say, "yes" or Click and give a treat.
Eventually during the pause, your dog will open his mouth. If your dog touches your skin with his teeth multiple times, say, "timeout" and put the toy away for a few minutes as a punishment. After a while, he will realize that the way to keep playing is to be gentler.