Why is my dog’s hair missing?

By DR. FRED SELF / Veterinarian

One of the questions we are asked in practice is why a client’s dog or cat is losing hair. Hair loss, also called alopecia, can have several causes.

This week we will highlight common causes in dogs. Next week we will highlight the common causes in cats. These are not complete lists of all the possible reasons for hair loss, they are the lists of causes we see the most.

The first cause of hair loss we look for when presented with a balding dog is fleas.

Fleas are common in the Southeast. Until proven otherwise, hair loss in dogs should be considered to be related to fleas. Even if the dog never goes outside and uses a flea control product, close inspection has to be made before moving on to the next possible cause. If no flea control product is being used, one should be started just in case. One flea can cause significant hair loss.

Another frequent cause of hair loss is allergies. Allergies can take several forms. The one most people think of is atopy, an allergy to something in the environment. Atopy can be caused by anything. The material in a dog bed, plants on the inside or outside of the house, carpet or upholstery cleaners and even human dander. Another form of allergy is food allergy. Food allergies are often associated with the protein in feeds. However, food allergies can be related to any component in a feed. There is no feed component with which all allergic pets will respond.

Mange is another condition that causes hair loss. There are two mange mites commonly seen in dogs. One called demodectic mange does not spread to other pets or people. It lives only on a single pet and causes damage to its hair follicles. The second mange is sarcoptic mange. It spreads to other pets and to humans. It causes hair loss by burrowing through the skin. Both forms can be treated, allowing the hair to regrow.

Ringworm also causes hair loss. Ringworm is caused by a fungus. The fungus can be picked up in the environment or spread from one pet to another or from pet to owner.

Most causes of hair loss have a treatment. It is important to start treatment as soon as possible and to understand that the treatment may be long term and, in the case of allergy, may have to be repeated annually.

Dr. Fred Self is a veterinarian at Shelbiana Animal Clinic in Columbiana, along with Dr. Charles Thornburg. You can reach the clinic at 669-7717.