What Causes Taurine Deficiency In Dogs? – Symptoms, Side Effects & Treatments

When I first started this blog I had certainly purchased my share of dog treats throughout my life but never really paid attention to any sort of trends in the pet food industry. Now that I’m much deeper into treats and foods that we give our dogs I’ve noticed an overwhelming shift towards grain-free pet foods and treats. Have you noticed?

I had assumed that it was a fad, kind of like a trend for us humans right now is to be gluten-free or carb-free. Things that happen for us humans tend to roll over into the pet industry because we believe what’s good for us must be good for pets as well.

Unfortunately, this is not always the case. Research is indicating that grain-free diets and other “trendy” diets for dogs may not be such a great thing and could be detrimental to your dog’s health.

Back Story

I’ve been having to try a lot of different diets to help relieve my oldest cats’ inflammatory bowel disease symptoms. When I took Wiley to the vet last week the veterinarian and I were discussing the different foods I have tried for him and in the process, the conversation turned to discussing grain-free diets for cats.

Since my puppy was with me, we naturally also began to discuss grain-free diets for dogs. What she had to tell me was really interesting and it is definitely worth your time to read on if you are feeding your dog a grain-free diet. The information here may also apply if you are feeding your dog a raw diet, vegan or vegetarian diet, or using a “boutique” dog food.

What’s the Problem?

It turns out research is indicating that grain-free dog foods, boutique foods, and foods made with what they consider to be “exotic” ingredients may be deficient in an amino acid called taurine. As dogs eat these foods over a period of time they develop a taurine deficiency which is leading to more and more dogs developing what’s called dilated cardiomyopathy (DCM), a heart condition that can cause congestive heart failure.

Dilated Cardiomyopathy

DCM is a disease of the heart muscle that causes the heart to have weak contractions and insufficient pumping ability. The disease eventually causes the chambers of the heart to become enlarged. One or more of the heart valves may begin to leak and signs of congestive heart failure develop.

What Is Taurine?

Just like there are amino acids that we need in our diet, there are amino acids that cats and dogs need in their diets too. Taurine is one of these amino acids.

Well, taurine is actually a sulfur-containing amino acid but quite often it is just referred to as an amino acid. Taurine is important in the metabolism of fats and plays an important role in maintaining good heart and eye function. Pet M.D. indicates that taurine is also important for the reproductive and gastrointestinal systems.

Cats and Taurine

It wasn’t determined until the 1990s why so many cats were developing severe eye problems and many were also dying from idiopathic DCM.


They figured out cats were getting these diseases because of a taurine deficiency. Cats are unable to synthesize taurine from other amino acids in their body so without it, they were developing feline central retinal degeneration (CRD) and/or dilated cardiomyopathy.

Taurine is now an essential or necessary amino acid for cats (it is essential that it be added to their diet).

Today’s “complete and balanced” cat foods are supplemented with taurine after the baking and processing phases of food production. For this reason, today’s quality foods including grain-free foods should provide sufficient amounts of taurine for your cat’s diet. But I’d still keep my eye on the cheap brands and check the labels!

According to the AAFCO and FDA, extruded (dry) cat food labeled as “complete and balanced” must contain 0.10% taurine and canned cat food should contain 0.20% taurine.

Dogs and Taurine

Unlike cats, dogs can make their own taurine from other amino acids in the body. For this reason, it is not considered an essential amino acid for dogs and is not required to be put back into dog food diets. This means that the laws don’t tell pet food manufacturers how much if any taurine to add to dog foods. There is no minimum requirement that manufacturers have to abide by.

It is been found that because of some baking, cooking, and/or processing methods or feeding incomplete raw, vegetarian, or boutique dog foods many dogs are being found to be deficient in taurine. This is especially likely for breeds such as the American Cocker Spaniel, Newfoundland, and Golden Retrievers.

Studies are showing that there are likely dietary factors associated with the taurine deficiency in dogs such as dogs that eat rice, lamb, high-fiber, and/or very low meat protein diets. This can point back to the preparation and/or processing methods used, or that many dog foods include meat by-products, rice, legumes, and soy which are not sources of good meat proteins or any meat protein at all, which means they are not good sources of taurine.

Lamb Meal and Rice Diets

Research is indicating that Newfoundlands, Golden retrievers, and giant breed dogs are more susceptible to taurine deficiency especially if being fed a commercially available food consisting of lamb meal, rice, or both as primary ingredients (Sanderson, S.,  2017).

The explanation of why researchers think lamb meal and rice diets are associated with an increased potential for taurine deficiency and DCM is a little long and detailed. You can reference the paper I listed in the above paragraph as well as a couple of others by accessing dropbox HERE.

Taurine Naturally in Foods

Muscle meats contain higher levels of taurine; the more work the muscles do, the higher the taurine level. The dark meat of chicken and turkey is naturally high in taurine. The heart is the hardest working muscle in anybody so it naturally contains high levels of taurine.

Shellfish, white fish, and cold-water fish such as salmon or sardines are also very high in natural taurine.

Taurine is not found in fruits, vegetables, rice, corn, oatmeal, rye, wheat, or barley.

Why is Taurine Missing?

Taurine (as well as other amino acids) found in the ingredients used to make pet food is often broken down during cooking and processing and therefore is not available or not recognizable for metabolism. Heat exposure during storage and transportation can also further destroy amino acids.

In addition, meat byproducts, rice, and plant-based proteins are not good sources of taurine. If your pet food has high quantities of these types of items, it likely means your dog is not getting the taurine it needs to be healthy.

With so many foods going grain-free, manufacturers are substituting the grain with things like lentils, soy protein, and chickpeas. These types of foods do not provide taurine to sustain good health.

Symptoms of DCM

DVM, Ernest Ward indicates DCM “may have a sudden onset of clinical signs, although the heart disease has been developing slowly and insidiously. Some dogs may develop severe congestive heart failure (CHF) in only a few hours”.

PetMD lists major symptoms of dilated cardiomyopathy to include:

  • Lethargy
  • Anorexia
  • rapid and excessive breathing
  • shortness of breath
  • coughing
  • abdominal distention
  • transient loss of consciousness

What to Do?

Gold is a Golden retriever and she has been on a grain-free diet for a while so all of this information kind of freaked me out.

If you’re worried about your dog having a taurine deficiency make an appointment with your dog’s veterinarian. When you go in for your appointment be sure to explain your concerns and also bring a bag of your dog’s food (if it’s easy enough to carry) or look up a really great picture of the back of the bag and bring it with you on your phone for your veterinarian to see.

If your veterinarian suspects a taurine deficiency and/or DCM tests can be performed. Once tests are performed they will guide you in the best way to move forward with getting your dog healthy.

The great news is once a taurine deficiency has been detected, the detrimental effects are often reversible by supplementing with taurine.

But, the first step is to examine the food you’re feeding your dog, determine if there is a possibility of taurine deficiency and get your dog to the vet.

Research hasn’t completely pinned down 100% of the reason for taurine deficiency in dogs, but one thing is for sure taurine deficiency can have a lot of bad repercussions. Be aware of what you are feeding your dog and if the bag does not tell you how much taurine is in the food – ASK!

Wishing everyone a happy, healthy, and taurine full day,

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