A pooch that likes to roll in stinky stuff puts a dent in the family bond — or at least in the number of dog hugs he receives. And yet, rolling in disgusting odors is normal behavior for some dogs.

The fact that putting on a stinky overcoat does not occur in most dogs, but in some frequently, suggests that it is either a crime of opportunity or an outdated instinct. Imagine this like an old computer program that was needed at one point, but now periodically pops up and causes problems. For this reason, I recommend neutering companion canines that frequently show this behavior, so we can gradually eliminate this instinct from the gene pool.

Because a roll in the hay is more natural to us than a roll in the stench, we can only guess at the original motivation. Here are some of the competing theories:

Disguise: This theory says that dog ancestors used "scent disguises" when hunting. The idea being that wolves wanted to hide their scents from their prey with a cover up like a person who uses heavy cologne instead of a shower.

Since wolves were near the top of the food chain, it is unlikely that they needed to hide themselves from predators, but that might have been a factor at some point. In either case, based on instinct, "It just seemed like the right thing to do at the time."

Territorial markers: In addition to other types of markers, wolves may have added their essence to an already powerful scent — like using a bullhorn instead of simply yelling. Normally, wolves use urine, fecal and dirt scratching to mark territory, but it is just as normal for one dog to "overmark" another's urine to add one's own scent to the previous passer-by who left his or her mark.

Contact high: Beauty is in the eye, or the nose, of the beholder. My favorite poop-rolling theory is that for some dogs, what is stench to us is their bliss. People are visual and see art largely with their eyes. Dogs might perceive scent art, and if so, some clearly have eclectic taste. For that scent-ual canine being, finding a rotting carcass might be like you or me finding a pile of free money. Gamblers that win big in Las Vegas are said to be rolling in money. Perhaps this expression originated from a literal event.

Any combination of these explanations may describe the original incentive but when your dog has this inclination you might want to be careful that a pattern doesn't develop and that you don't inadvertently reinforce this behavior.

If you catch Fido in the act of rolling in canine riches, interrupt the behavior and then ask him to do something positive, like sitting or coming to you, so you can reward compliance. Increase praise for alternative behaviors such as these and for walking by your side to diminish the impact of the attention you give to Fido when he rolls in funky stuff. Remember that negative attention is still attention.

If Fido is off leash and you see him heading for some foul target, if you think he will come to you, call him. Otherwise, whoop it up and run in the opposite direction to get him intrigued enough to follow. Once he is running toward you, say, "Come," and praise like this is his "second coming." Then pull a treat from your pocket if you have one and if not praise and give lot pats as if he just won the Pulitzer.

If he leaves the stench to come to you when called, ignore the recent bad behavior, and praise the current good response. Generally, once a dog is already going in for a stinky landing, there is no stopping him. But if you can get his attention during the "thinking about it phase" you'll have a better chance.

If your dog has this habit, veterinarian Dr. Gary Landsberg, from the Doncaster Animal Clinic, recommends, "Walk your dog on a long leash with a head halter to make it easier to interrupt the rolling before it starts." If not, be prepared for the occasional bath after the fact.

To make it easier to accept this canine conundrum, just keep thinking about yourself rolling in all that cash.

When out on a walk, begin calling Fido to you when he is not focused on anything to reinforce a positive pattern of giving praise when he comes and sits for you. Give a treat if he sits close enough that you can also touch his collar. Otherwise, he might learn to run off when you reach for him. Try for at least 10 recalls on each off-leash walk. If you don't have a treat, substitute "heavy petting" as a reward.

Also consider having him drag a 20-foot lead that you can step on if he ignores you. This makes it easier to insist that he come and sit. Back up and repeat this sequence several times for practice. Praise lavishly to develop a happy worker.

He should eventually realize that if he comes to you, he gets to go free again immediately, but if he doesn't come it means several minutes of intensive work. Add a favored food or toy reward for your dog's best responses.