How Do Dogs Shed?

All dogs, except hairless dogs, shed; even dogs advertised as nonshedding dogs shed. Dogs thought to be nonshedding simply do not shed as much or as often as dogs thought to be shedders, and dogs with longer hair do not shed more than their shorter-haired counterparts but simply shed, well, longer pieces of hair. A dog's old hair must be replaced with new hair. In the wild, dogs are regularly brushing up against trees and other objects, which helps the shedding process. Dog owners may see Fido rubbing his side along the bottom of the couch to simulate the experience now remembered only by his genes.

Shedding is important because it replaces old, dirty hair with new, clean hair. A dog's coat is kept healthy this way. Owners who brush their dogs regularly help control their dog's shedding process by catching thousands of hairs in a brush instead of in a vacuum cleaner or dust pan or on their clothes. Dogs whose owners brush them daily to control the hairs being lost often smell better too---the more dirty hairs are encouraged to leave the body, the more cleaner hairs are encouraged to grow on it.

How long the hair grows before falling out and being replaced and how often the falling-out-and-replacing process occurs depend on genetics and environment. Some dogs shed all year long, while others shed seasonally. Outdoor dogs usually grow a thick winter coat to keep warm when the temperature outside drops; this undercoat must come off in the spring when the weather turns warm. Losing this winter layer of hair is called "blowing" a coat. It is no mystery when dogs with lots of longer hair, such as malamutes, are blowing their winter coats: Dog hair is absolutely everywhere. Indoor dogs experience more consistent temperatures and therefore may not shed large amounts of hair each spring but small amounts of hair all year long.

Shedding may be caused by forces other than genes and living conditions. Dogs who live stressful lives will sometimes shed as a result. So may dogs who have ringworm or cancer. If your dog begins to shed at odd times of the year or in unusual amounts, consider visiting your veterinarian. It might be a sign of a health issue.

Resources

• American Kennel Club grooming recommendations