Dilated Cardiomyopathy in Cocker Spaniels: My Story, Part 6

Posted on May 30, 2025May 30, 2025 by Julia Morton

New Research: The CURE Project from Sweden

In August 2024, Swedish researchers published a study titled “The Canine taURinE (CURE) Project,” investigating low blood taurine levels in English Cocker Spaniels and their association with clinical signs of dilated cardiomyopathy (DCM) and diet.

The study focused on DCM2 — the form of DCM believed to be linked to nutrition — and included both healthy dogs and those with DCM or congestive heart failure (CHF). Of the 180 dogs studied, 13 were diagnosed with CHF. (1)

Key Findings:

29% of dogs had low blood taurine concentrations
25% of those with low taurine showed clinical signs of CHF
9% of taurine-deficient dogs exhibited retinal abnormalities

The researchers analyzed 60 commercial dog foods, discovering a clear link between taurine levels and the amino acid profile of each diet. Diets rich in white meat proteins had higher taurine levels than those using red meats. Lamb, in particular, was found to be low in methionine and cysteine, precursors needed to synthesize taurine.

Conclusion:

Taurine supplementation may help prevent the onset of DCM and retinal issues in English Cocker Spaniels.

A Closer Look at Taurine Deficiency and DCM

What struck me most was that all 13 English Cocker Spaniels diagnosed with CHF had very low blood taurine levels. This suggests a potential link — but not a guarantee.

Interestingly, in a personal email exchange with Mark D. Kittleson, DVM, PhD, DACVIM, he shared that during the MUST study, a cardiologist in England submitted 10 samples from English Cocker Spaniels with DCM — and none were taurine deficient.

This highlights an important point: DCM isn’t always caused by taurine deficiency, even within the same breed.

Raw Diets Were Not Included in the Study

One limitation of the CURE study was the exclusion of raw food diets due to concerns about inconsistent nutrient content:

“Samples from raw food diets were not collected for analysis because of the inconsistent content between batches in such diets.”

As someone who feeds a raw diet, this stood out. I contacted Big Country Raw, the brand I’ve used since Allie was a puppy. Here’s what they shared:

“Since taurine is naturally high in meat and organ meat, every raw recipe that is not extremely high in fat or bones will bring plenty of taurine, even if batches vary. In the testing we did, we were on average at 4x the requirements. It was different from one protein to another based on natural content, but always largely over the requirements.

At Big Country Raw, we are doing mixing validation studies to ensure that levels of nutrients are stable within a batch, from one batch to another, and from one supplier to another. “

DCM Prevalence in English Cocker Spaniels: Regional Differences

The Swedish researchers noted that English Cocker Spaniels are overrepresented in DCM cases. However, veterinary professionals I’ve spoken with in the United States say the breed’s DCM rate isn’t high enough to justify genetic research. This could reflect differences in breeding lines or regional diets.

Omega-3 and Vitamin E Supplementation

At a 2024 veterinary seminar, Meg Sleeper, VMD, DACVIM, presented compelling research on the benefits of Omega-3 fatty acids for heart health. She emphasized using fish oil, with a dosage based on weight:

EPA: 40 mg/kg/day
DHA: 25 mg/kg/day

For Allie, who weighs 10 kg, this means:

400 mg EPA
250 mg DHA

Benefits of EPA/DHA for Heart Health:

Reduces systemic inflammation
Stabilizes heart rhythms (reduces arrhythmias)
Improves blood vessel function and circulation

In Part 5 of this blog series, I noted a study showing that many dogs with DCM are vitamin E deficient. Whole Dog Journal also reported that fish oil can deplete vitamin E over time. As a precaution, I’ve added 400 IU of vitamin E daily to Allie’s routine alongside her Omega-3s. (2)

Grain-Free Diets and Taurine: Not the Culprit

Since the FDA halted its investigation into grain-free diets and DCM, several studies have emerged indicating that grain-free diets do not cause taurine deficiency.

What the Research Shows:

“The Pulse of It” Study
Involved 28 Siberian Huskies on a diet with up to 45% pulses for 20 weeks. There were no negative changes in heart function or cardiac markers. All dogs remained healthy and off cardiac medications. (3)
Journal of Animal Science Review
A literature review of 150 studies found no definitive link between grain-free, legume-rich diets and DCM. (4)
Taurine Levels in English Cocker Spaniels
A study examined 20 English Cocker Spaniels on grain-free vs. grain-inclusive diets. Dogs on grain-free diets had slightly lower taurine levels, but the difference was not statistically significant.
Interestingly, dogs eating lamb had notably lower taurine, regardless of grain content. (5)

Allie’s Health Update

In February 2025, Allie had another echocardiogram — and I’m happy to report she’s holding steady.

While she still shows mild signs of DCM, she remains asymptomatic. True to her breed, she’s bursting with energy — enjoying off-leash hikes, running full speed through the forest, and sports like agility and tracking. Her littermate is also doing well, with similar results from her latest echocardiogram. One other littermate has since had an echocardiogram, and is normal.

I monitor her resting respiration rate daily and schedule regular echocardiograms to stay ahead of any changes.

Final Thoughts

This new research highlights the complexity of DCM and taurine deficiency, particularly in English Cocker Spaniels. While taurine clearly plays a role in some cases, it’s not the whole story.

I encourage pet owners to:

Consult with a veterinary cardiologist if DCM is suspected
Choose nutrient-rich diets, whether commercial or raw
Consider Omega-3 and vitamin E supplementation under veterinary guidance
Stay informed and be an advocate for your dog’s heart health

If you’ve had a similar experience or have questions about taurine, DCM, or diet, feel free to leave a comment or email me!

References

(1) Kriström K, Häggström J, Fascetti AJ, et al. The association between taurine concentrations and dog characteristics, clinical variables, and diet in English cocker spaniels: The Canine taURinE (CURE) project. J Vet Intern Med. 2024;38(5):2620‐2632. doi:10.1111/jvim.17150

(2) Whole Dog Journal https://www.whole-dog-journal.com/health/vitamin-e-for-is-good-for-dogs/

(3) Singh, Pawanpreet, et al. “The Pulse of It: Dietary Inclusion of up to 45% Whole Pulse Ingredients with Chicken Meal and Pea Starch in a Complete and Balanced Diet Does Not Affect Cardiac Function, Fasted Sulfur Amino Acid Status, or Other Gross Measures of Health in Adult Dogs.” The Journal of Nutrition, 25 Mar. 2023, www.sciencedirect.com/science/article/pii/S0022316623355007, https://doi.org/10.1016/j.tjnut.2023.03.027.

(4) News, Veterinary Practice. “Grain-Free Diet Not Linked to DCM in Dogs, Research Review Finds.” Veterinary Practice News, 22 June 2020, www.veterinarypracticenews.com/grain-diet-not-linked-to-dcm-in-dogs-study-says. Accessed 30 May 2025.

(5) INFLUENCE OF A GRAIN-FREE DIET ON THE BLOOD PLASMA TAURINE CONCENTRATION IN ENGLISH COCKER SPANIELS (final Thesis) https://dspace.emu.ee/server/api/core/bitstreams/bd6d1a79-4b01-427d-8fc3-d8fb088d5b62/content