- Type Disease
Colour Dilution Alopecia
This condition develops in some, but not all dogs that have been bred for unusual coat color, especially fawn (a dilution of a normally red or brown coat) or blue ( a dilution of the normal black and tan coat color). Alopecia means hairlessness - affected dogs have a poor, patchy hair coat progressing to widespread permanent hair loss. At the cellular level, there are abnormalities of the hair follicles and uneven clumping of pigment (melanin) granules in the hair shafts in affected areas
- How Transferred
The inheritance is unclear. The condition is thought to be due to the interaction of different factors at the gene position for color. It is not simply determined by the genes at that locus, because not all dogs with color dilution develop coat problems.
- What to Look for
Dogs with this condition are born with a normal hair coat. Those with lighter blue or fawn hair coats usually start to show changes by 6 months while in dogs with darker steel blue coats, the changes may not be evident until 2 or 3 years of age. Your dog will experience hair loss and dry skin. Sometimes the earliest sign is a recurring bacterial infection (folliculitis), generally on the back, where you will see small bumps which are infected hair follicles. This clears up temporarily with antibiotics, but the affected area is very slow to regrow hair, or remains hairless.\nHair loss is usually first apparent on the back and by 2 or 3 years has spread over all the light colored areas of the body. The exposed skin is often scaly and is susceptible to sunburn or extreme cold. Your dog's health is not otherwise affected by this condition.
Your veterinarian may suspect this disorder if your dog has typical hair coat changes and is an unusual color for the breed. The diagnosis is confirmed through microscopic examination of plucked hairs or a skin biopsy. The latter is a simple procedure, done with local anesthetic, in which your veterinarian removes a small sample of your dog's skin for examination by a veterinary pathologist. The biopsy will show changes characteristic of this condition.
Your dog can lead a normal healthy life with periodic symptomatic treatment as needed - moisturizing rinses for dry scaly skin or antibiotics for bacterial infections.\nSince early hair loss occurs due to breakage, you may be able to slow the rate of loss by avoiding harsh shampoos and vigorous grooming.\nFor the veterinarian: There have been some early reports of hair regrowth using etretinate treatment . (See resource below.)
- Veterinarian Information
Your dog can lead a normal healthy life with periodic symptomatic treatment as needed - moisturizing rinses for dry scaly skin or antibiotics for bacterial infections.\nSince early hair loss occurs due to breakage, you may be able to slow the rate of loss by avoiding harsh shampoos and vigorous grooming.\nFor the veterinarian: There have been some early reports of hair regrowth using etretinate treatment .
- Breeding Considerations
Affected dogs, their parents and siblings should not be used for breeding. The condition can be entirely avoided by the use of non-color-diluted dogs in breeding programs.
- Known Breeds Affected
Bernese mountain dog\nChihuahua\nChow chow\nDoberman pinscher\nIrish setter\nMiniature pinscher\nPoodle, standard\nSaluki\nSchipperke\nShetland sheepdog\nWhippet\nYorkshire terrier\nDachshund\nPortuguese water dog\nSilky terrier