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Vitamin D Deficiency in Dogs and Cats

Overview of Vitamin D Deficiency in Dogs

Vitamin D is an essential vitamin for dogs and deficiency can lead to problems. Vitamin D regulates calcium and phosphorus absorption and muscles, nerves and bones require vitamin D to function properly.

Vitamin D deficiency, also known as hypovitaminosis D, can occur in dogs due to several reasons. They include:

In people, vitamin D deficiency has been associated with high blood pressure, cancer, diabetes, heart disease, asthma, rickets, infections, depression, and other problems. The same is suspected in dogs and cats, although research in this area has been lacking.

When a dog is deficient in Vitamin D, the muscles may not work normally. One important muscle that can be affected is the heart muscle. Vitamin D deficiency can cause congestive heart failure that can be fatal.

What to Watch For

Vitamin D deficiency in dogs and cats is believed to be associated with cancer, heart failure, kidney disease, infections, inflammatory bowel disease (IBD), rickets, and potentially feline teeth problems (feline oral resorptive lesions). Additional research in this area is needed to help us better understand the impact of deficiency on both dogs and cats.

Vitamin D deficiency in dogs can cause heart failure, muscle aches, muscle weakness, bone pain, hair loss, fatigue, poor wound healing, and/or lethargy.

The most significant signs of vitamin D deficiency in dogs are those of heart failure. A poorly functioning heart can cause coughing, lethargy, weakness, exercise intolerance, weight loss, and/or difficulty breathing. Learn more about Dilated Cardiomyopathy (DCM) in Dogs.

Diagnosis of Vitamin D Deficiency

A complete physical exam will be done and your veterinarian will pay particular attention to the heart and bones. Diagnosis will depend on your dog’s history, clinical findings and a blood test.

It is believed that normal vitamin D3 levels in dogs are 100 to 120 ng/mL. Deficiency is defined as less than 100 ng/mL.

Treatment of Vitamin D Deficiency

Treatment will depend on the underlying cause of the deficiency. Many efforts focus on increasing the dietary vitamin D ingestion by feeding a high-quality dog food. The Association of American Feed Control Officials (AAFCO) recommends that adult dog food provide 500 IU of Vitamin D per kilogram of food. Food companies that follow these guidelines indicate that their food is AAFCO compliant on the bag. Foods that are good sources of Vitamin D include fish such as salmon, herring and mackerel, liver, egg yolks, beef, and dairy products.

Disorders that cause vitamin D deficiency such as those that impair the absorption or metabolite conversion will require different testing and treatments.

Ultraviolet B rays from sunlight are a large source of vitamin D in people but are not regarded as important in dogs. This may due to their hair coat preventing ultraviolet absorption.

Recommendations regarding supplementation with vitamin D is varied and controversial amongst veterinarians. Much is still unknown about vitamin D deficiency and its impact. It is important NOT to overdose the Vitamin D.

Home Care

There is a lot not known about vitamin D deficiency in dogs. Recent research in humans has revealed that vitamin D is critical for bone health as well as decreases the risk of some diseases. Some foods are supplemented with vitamin D such as milk but many people are still deficient and are prescribed supplements. Many believe that dogs may also be deficient.

Be careful to not give too much Vitamin D because it is a fat-soluble vitamin that can lead to toxicity if you overdose. Providing your dog with a healthy multi-vitamin is a great way to ensure that your dog is receiving all of the vitamins they need inappropriately balanced levels.

Provide your dog with all the recommended supplements and diets.

Prevention of Vitamin D Deficiency in Dogs

The best way to prevent Vitamin D Deficiency in dogs is to feed a high-quality diet, perform blood testing as recommended by your vet and giving vitamin D supplements as recommended. Additional research is needed to help veterinarians determine the full impact of Vitamin D Deficiency in dogs.