Puppy aggression

Question
We have a 13 week old black lab puppy in a very busy household.  Most times he is sweet and gentle, however, when we play with him, he displays aggressive behavior.  The puppy biting goes to the next level and it's very difficult to stop.  He will lunge at you, growl and keep coming back for more.  We've tried firm "no", distracting with toys, grabbing the scruff of his neck, walking away.  He will bark and go back at you.  I don't want this behavior to escalate and would like to nip it in the bud before it happens.  Any suggestions?

Answer
The key to most behavior problems is approaching things using the dog's natural instincts. Dogs see all the people and dogs in the household as a pack with each having their own rank in the pack and a top dog. Life is much easier if the 2 legged pack members outrank the 4 legged ones. You can learn to play the role of top dog by reading some books or going to a good obedience class. A good obedience class or book is about you being top dog, not about rewarding standard commands with a treat.

Young Labs, which I know best, and other puppies tend to very bad about biting. You see a litter of them, and all the ones that are awake are biting another one or themselves. I am not even sure they realize that when they are alone, if they quit biting, they would quit being bitten. At 3 to 4 months they are getting their adult teeth, and it seems they spend every waking moment biting or chewing. One thing you can do at that stage is to knot and wet a piece of cloth. Then freeze it. The cooling will soothe the gums. Only let the puppy have it when you are there to watch it. I maintain a Lab's favorite chew toy is another Lab. Otherwise they settle for any person they can. They keep hoping to find one that won't yelp, jerk their hand away, and leave.

You just have to keep on correcting them, hundreds of times, not dozens. Provide sturdy, safe toys such as Kongs and Nylabones. Avoid things they can chew pieces off and choke on them. Keep them away from electrical cords. Crates are essential for most young Labs and other dogs.

The pet stores are full of toys that many dogs will quickly chew up into pieces they could choke on or cause intestinal blockages. If you are not there to watch, stick to sturdy stuff such as Nylabones and Kongs. Keep a close eye on chew toys and quickly discard anything that is coming apart in pieces. Rawhide is especially bad because it swells after being swallowed. I don't trust any of the consumable chews. The dogs just gnaw them down to a dangerous size too quickly. These problems are the worst with, but not limited to, large, aggressive chewers such as Labs.