Genetic Hair Disorder

Color Dilution Alopecia (CDA)

Bayland Flint
Bayland Flint
Bayland Flint - bald ears

Although it is not often advertised by breeders, Color Dilution Alopecia does affect Koolies.

Unfortunately, there currently are breeders in Europe knowingly pairing carriers of the disease, so if you are looking to get a puppy in Europe, make sure to ask the breeder in question about the D gene specifically and what they are actively doing to keep their lines healthy.

Color Dilution Alopecia (CDA) is a genetic hair disorder that primarily affects certain dog breeds. It is characterised by hair loss and skin problems in dogs with diluted coat colours, such as blue, fawn, or Isabella. This condition can be distressing for both the dogs and their owners. The disease is often labelled a cosmetic disease, but that doesn’t mean it doesn’t require proper understanding, dedication, and management for affected dogs to live happy lives.

The current advice is to not breed with the parents of a litter affected with CDA but also that none of the siblings of a litter with a dog with CDA should be used for breeding as they will all be carriers.

The genetics of CDA involves the interaction of two genes: D (Dominant) and d (Recessive). These genes determine the intensity of pigmentation in the coat of dogs.

The D gene is responsible for normal pigmentation, while the d gene is associated with diluted pigmentation. A dog can have one of three possible combinations of these genes: DD, Dd, or dd.

Dogs with the genotype DD have normal pigmentation and do not carry the gene mutation associated with CDA.

Dogs with the genotype Dd have normal pigmentation but carry one copy of the mutated gene. They are considered carriers and can pass the mutated gene to their offspring.

Dogs with the genotype dd have diluted pigmentation due to the presence of two copies of the mutated gene. These dogs are at risk of developing Color Dilution Alopecia.

When two carriers (Dd) are bred together, there is a 25% chance that their offspring will inherit the mutated gene from both parents and develop Color Dilution Alopecia (dd genotype). This is why careful breeding practices and genetic testing are important to reduce the risk of CDA.

Note: The genetics of CDA can be more complex with multiple genes involved, but the simplified explanation above provides a basic understanding of how the D and d genes contribute to the development of Color Dilution Alopecia.

Color Dilution Alopecia (CDA) is characterised by a range of symptoms that primarily affect dogs with diluted coat colours. Common symptoms of CDA include:

Gradual hair loss: Hair loss typically starts on the head and may extend to other areas of the body, such as the trunk, neck, and tail. The hair loss is limited to the dilute colour, so other colour hairs will look healthy in comparison.

Thin and brittle hair: Affected dogs may have hair that is thin, weak, and easily breakable. The hair shafts may become fragile and prone to damage.

Discoloured skin: The skin may exhibit a greyish or pinkish hue, which is a result of the dilution of pigment due to the genetic mutation associated with CDA.

Dry and flaky skin: Dogs with CDA may experience dryness and flakiness of the skin, leading to itchiness and discomfort.

Skin inflammation and irritation: The affected skin may become red, inflamed, and sensitive, causing discomfort and potentially leading to scratching or rubbing.

Dogs with CDA often suffer from secondary infections. Due to the compromised skin barrier, affected dogs are more prone to infections, such as bacterial or fungal infections.

It’s important to note that the severity and progression of symptoms may vary among individual dogs with CDA. Some dogs don’t show any symptoms until they are two years old, while others already show symptoms at eight weeks.

Diagnosing Color Dilution Alopecia (CDA) typically involves a combination of clinical examination, medical history assessment, and diagnostic tests. Here are the common steps involved in the diagnosis:

  • Physical Examination: A veterinarian will examine the dog’s coat and skin, looking for characteristic signs of CDA, such as hair thinning, hair loss, skin discolouration, and skin inflammation. They will also assess the overall health of the dog.
  • Medical History: The vet will inquire about the dog’s medical history, including any observed changes in the coat, previous skin conditions, and information about the dog’s breed and lineage.
  • Skin Biopsy: In some cases, a skin biopsy may be performed to confirm the diagnosis. A small sample of skin is collected and examined under a microscope to assess the hair follicles and confirm the presence of characteristic changes associated with CDA.
  • Genetic Testing: Genetic testing can be conducted to identify the presence of the specific gene mutation associated with CDA. This testing can help determine if a dog is a carrier or affected by CDA. It is especially useful for breeders to make informed breeding decisions.

By combining these diagnostic approaches, veterinarians can accurately diagnose Color Dilution Alopecia and differentiate it from other skin conditions that may present with similar symptoms. If you suspect your Koolie has CDA, make sure you consult a veterinarian who is experienced in dermatology or genetic disorders for an accurate diagnosis and appropriate management plan.

While there is no cure for Color Dilution Alopecia (CDA), there are several treatment approaches that can help manage the condition and improve the well-being of affected dogs. It’s important to note that treatment effectiveness can vary among individuals, and not all dogs will respond in the same way. Here are some common treatment options:

Symptomatic Management: Managing the symptoms associated with CDA can help improve the dog’s comfort and minimize secondary complications. This may include using specialized shampoos and conditioners to soothe the skin, reduce inflammation, and prevent infections. Your veterinarian may recommend specific products suitable for dogs with sensitive skin.

Nutritional Support: Providing a balanced and high-quality diet is essential for the overall health of the dog. Including essential nutrients, such as omega-3 fatty acids, can help support skin health and improve the condition of the coat. Your veterinarian can recommend appropriate dietary supplements or specialized diets.

Sun Protection: Dogs with CDA are more susceptible to sunburn and skin damage. Providing shade and using pet-safe sunscreen on exposed areas can help protect the skin from harmful UV rays.

Avoiding Skin Irritants: Minimizing exposure to potential irritants, such as harsh chemicals or grooming products, can help prevent further damage to the already fragile hair and sensitive skin.

Regular Grooming: Regular and gentle grooming practices, such as brushing, can help manage shedding, prevent matting, and remove loose and damaged hair. However, care should be taken to avoid excessive brushing or grooming, which can further weaken the hair shafts.

Emotional Support: Dealing with a chronic condition like CDA can be emotionally challenging for both the dog and the owner. Providing a loving and supportive environment, enriched with mental stimulation and physical exercise, can help maintain the dog’s overall well-being.

It’s important to consult with a veterinarian who has experience with dermatological conditions or genetic disorders for an individualized treatment plan tailored to your dog’s specific needs. They can assess the severity of the condition, recommend appropriate treatments, and provide guidance on long-term management strategies.

Share Your Story!

Do you have a personal experience with a Koolie that suffered from CDA? We would love to hear from you! By sharing your story on our website, you can contribute to educating and providing valuable insights to fellow Koolie owners facing similar challenges. Together, we can help support ethical breeding and help keep the amazing Koolie breed healthy.