Is he trying to tell you something?

While it may seem like a good life-lying around the house all day, getting free meals-it's not easy being a dog surrounded by humans. Too often, we assume they understand us better than they do. And too often we don't understand them, assuming they can switch off their species' instincts and become 4-legged, furry humans.

A surprise bearing of teeth, a slight growl, perhaps even a nip at you �?these may be warning signs. He's telling you he's not comfortable with the situation. So it's a defensive behavior. But we humans may interpret this as aggression or disobedience and respond by escalating his discomfort with a confrontation.

Notice the cycle: he's being defensive and we respond by "attacking" with a raised voice or, worse still, punishment.

We need to understand that even though these gestures may seem intimidating they're probably the only way he has to tell you everything's not okay. Consider. The warning nip rarely breaks the skin

What is setting his reaction off?

Pain - Remember the old fable of the lion with a thorn in its foot. Perhaps your dog has a physical condition you're not aware of. For instance, many breeds are susceptible to hip dysplasia. It's a painful condition that only worsens as dogs grow and age. "Sudden" mood swings may actually have always been there but it just took till he was older for you to notice.

Talk to your vet. If it's a chronic condition, there may be medications that make it easier for your dog to live with. You may need to stop playing certain games with him that trigger the pain and the consequent warning signs.

Age - Sudden aggressive tendencies are not uncommon in older dogs. It's often an early sign of senility. Again, talk to your vet. For extreme conditions, there are medications to ease the condition 

Rescued dogs - Most experts will tell you that 99.9% of dogs are trainable. This even goes for dogs who've been abused before they come to you. Some rescue dogs have trouble trusting humans. When you react to his defensiveness with greater aggression it only promotes his fear and reinforces his behavior.

You have to rebuild the bonds of trust. Dogs need a lot of love and a strong relationship may take time. Punishment is the worst thing you can do. When you see defensive signs, assume non-threatening body language. Make a whining noise like those you hear from a nipped pup. It says that now you have become nervous of his behavior, and you're backing down.

Backing down from a confrontation is a good beginning of trust between two parties. Chances are he'll do the same. Perhaps he'll even assume a submissive position, like lying on his back, exposing his vulnerable belly.

If he doesn't the first few times, be very patient. Walk away from him slowly and calmly. A timeout is an excellent demonstration that playtime is over and you're not being threatening.

Eventually he'll come around. You'll be able to approach, pet and play with him. Take the time to understand him and you'll both feel better.