According to legend, God bestowed cold, wet noses on dogs for saving Noah's Ark from sinking. As the story goes, a dog was on patrol when he discovered water pouring through a hole in the hull. The quick-witted dog stuck his nose in the small hole to keep water from flooding in.

The second dog ran off to alert Noah, who quickly repaired the hole. The dogs saved the day. For their actions, God made a cold, wet nose the symbol of good health for a dog.

However, while this is often true, it's not the best barometer for health and should not be relied on. Although most people say a healthy nose should be "cold and wet," it is actually more appropriate to describe it as moist. A wet, runny nose is a sign of trouble and should be checked out by a veterinarian. By the way, a normal moist nose doesn't always mean a dog is healthy; if your dog has a moist nose but seems lethargic, or in discomfort or pain, consult your vet.

Conversely, a dry nose doesn't always signal illness. Dogs just waking from sleep often have a warm, relatively dry nose. And, some dogs, like bulldogs, just have dry noses that even chap and crack.

Despite what many people think, you cannot determine your dog's temperature by feeling his nose. A warm nose does not mean your dog has a fever. Only a properly used thermometer can tell you that. So remember, if your dog shows discomfort, lethargy or loss of appetite, you'll need to have your local vet examine him, regardless of the condition of his nose.

If you see a nasal discharge, swelling, or detect unpleasant odors emanating from your dog's nose, or if he has difficulty breathing, get him checked out right away. It could mean the presence of a foreign object, tumor or infection.