Taurine, Dcm, And Grain-free Diet Issues In Dogs And Cats

by Dr. Hannah Godfrey BVetMed MRCVS of The Vets

Dilated Cardiomyopathy (DCM) is a condition that affects the heart in both dogs and cats. In DCM, the walls of the heart do not contract much and therefore struggle to squeeze the blood out of the heart chambers, around the body, and to the lungs. But what causes DCM? And can it sometimes be prevented?

Causes of Dilated Cardiomyopathy

Veterinarians have long been aware of the link between certain breeds of dogs and the condition Dilated Cardiomyopathy (DCM). Some breeds which appear to be more prone to DCM include Cocker Spaniels, Dobermanns, Golden Retrievers, Boxers, Great Danes, Irish Wolfhounds, German Shepherds, and Newfoundlands. Initially, the link was considered primarily genetic, however, more recently it has become clear that there are other factors.

Genetic Dilated Cardiomyopathy

Dog breeds that are genetically predisposed to DCM tend to be large or giant breeds and include Dobermanns, Great Danes, Irish Wolfhounds, and Boxers. However, Boxers commonly get an atypical form involving Arrhythmogenic Right Ventricular Cardiomyopathy, also known as ‘Boxer cardiomyopathy’. Predisposed breeds can now be screened for DCM, to start treatment before signs occur and reduce the use of affected dogs for breeding.

Taurine deficiency

Taurine is an amino acid that most dogs will receive within their diet, as long as the diet is nutritionally complete. They can also make taurine in their body, from other amino acids, if needed. A lack of taurine or sufficient amino acids within the diet can lead to taurine deficiency, which is a cause of DCM in dogs.

Although certain breeds, like Cocker Spaniels, are predisposed to developing DCM due to taurine deficiency, many cases of DCM in other breeds have also been found to have low taurine. Therefore, even without a predisposition to developing DCM, dogs with a nutritionally incomplete diet may develop DCM due to low taurine levels. Supplementation with taurine has been shown to improve heart function in some dogs with DCM related to taurine deficiency.

L-carnitine deficiency

Carnitine is made within the body from two amino acids, lysine and methionine. Up to 40% of dogs with cardiomyopathy could have low carnitine, although it doesn't always show up on blood testing. This is because the heart cells may not have sufficient carnitine even if the overall level of carnitine in the blood is normal. Boxers appear to be especially prone to carnitine deficiency, but other dogs with DCM have incidentally been found to have low carnitine, and have responded to carnitine supplementation.

Causes of Dilated Cardiomyopathy in Cats

In cats, taurine is an essential amino acid, meaning that they cannot make it within their bodies from other amino acids and it must be provided within their diet. Without a diet containing sufficient taurine, cats will also develop DCM.

What diets might put your dog or cat at risk of DCM?

Since we now know that taurine deficiency and carnitine deficiency are factors in the development of DCM, we can conclude that diet is very important. Various diets have been investigated recently to determine if there is a link between them and DCM. Although it is not yet proven that grain-free diets lead to an increased risk of DCM, there are concerns about a potential link.

Grain-free, homemade, and boutique diets

Any diet that is not a commercial, certified complete pet food runs the risk of not containing the correct balance of vital nutrients that your pet needs and sadly this can have serious consequences. The risk with grain-free diets is that they contain a higher proportion of leguminous vegetables that may replace other more nutritionally valuable ingredients, making your pet more prone to deficiencies. Data suggests that some dogs with DCM who were not otherwise predisposed had been fed a grain-free diet, although the true link is not yet clear.

For the same reasons, deficiencies are also a concern with vegetarian, vegan, home-formulated, or unregulated boutique diets, since they may not provide the levels of taurine, other amino acids, and other nutrients that your pet needs to stay healthy. More information on the potential links between these diets and DCM can be found here.

So, what can I do to try to reduce my pet’s risk of DCM?

The first and most important thing that you can do to keep your dog or cat as healthy as possible is to feed them a regulated, nutritionally complete pet food that is formulated for their species. For a pet food to be complete it should be formulated according to the Association of American Feed Control Officials’ standards, as well as following the Global Nutrition Guidelines set out by the World Small Animal Veterinary Association. Feeding your pet a complete diet won’t just reduce their risk of DCM caused by deficiencies, but it will help ensure their overall health.

It is also sensible to ensure your pet is booked in for a regular, routine health check with your veterinarian. Ideally, this would be once a year at least and it can be performed during their vaccination appointment. If your veterinarian discovers a heart murmur or has other concerns during the examination, they may recommend a heart scan, blood test, or other investigation to determine whether medication is needed.

Finally, if your dog is a breed that is predisposed to DCM, screening can be performed every six to twelve months. Dogs with DCM often show no symptoms until the condition has become life-threatening, so screening allows it to be picked up early, as well as reducing the use of affected dogs for breeding.

By following the above advice, you will ensure that you are not inadvertently increasing your pet’s risk of developing DCM, or another nutritional condition.


About The Author
Dr Hannah Godfrey graduated from the Royal Veterinary College in 2011. She has worked solely with pets since 2014, and has gained a wealth of experience in that time! Aside from writing for The Vets and being a vet, Hannah enjoys running, baking, and spending time with her cats – Poppy and Ashton Kutcher.