Cold nose not always health indicator

Q: I'm confused about why my dog Sam's nose is occasionally warm and dry, even though he seems fine. I thought a dog in good health always had a cold, wet nose.

A: Sam's nose is usually cold and wet for two reasons.

First, nasal glands inside his nose produce a watery liquid that cools and dampens the lining of his nasal passages and the surface of his nose. Scent molecules stick to this nasal moisture, enhancing his sense of smell. Nasal gland secretions also contain antibodies that protect him from disease.

Second, the tears produced by the lacrimal glands bathe the surface of each eye and then drain through tiny openings, called puncta, at the inner corner of each eyelid. From there, the tears drain down the nasolacrimal ducts in the muzzle and out through the nostrils.

The tears tickle, making Sam lick his nose. As the tears and saliva evaporate, the surface of his nose cools. Nasal glands and tear glands cut back their production when dogs sleep. My guess is that Sam's nose is warm and dry only when he awakens from sleep.

Other reasons for a dry, warm nose include a reduction in nasal secretions, decreased production of tears, and blockage of the puncta or nasolacrimal ducts, causing the tears to spill over the eyelids rather than drain through the nose.

In short, you can't tell anything about Sam's health based on the temperature or dampness of his nose. A warm nose doesn't mean he has a fever any more than a dry nose indicates dehydration.

Whenever you're concerned about Sam's health, take him to his veterinarian for a thorough physical exam so you'll know what's happening. In the meantime, I find that regularly kissing my dog's nose keeps him—and me—happy.

Editor’s Note: Dogs and cats can catch cold, though the viruses that cause cold symptoms in pets differ from those that affect humans. Knowing the signs and symptoms can help you decide whether your pet has a simple cold or a more serious health problem.

Lee Pickett, V.M.D. practices companion animal medicine in North Carolina. Contact her at vet@askthevet.pet.