There was a discussion about this issue a short while ago here on DT: https://www.dobermantalk.com/doberma...1-taurine.html
In the thread I linked, one of my comments has a link to a presentation that is public on Facebook by a veterinary cardiologist to the Doberman Club of Dallas. She does briefly discuss this issue.
Basically, the theory is that the heavy legume/pea content that is used in most grain-free foods is somehow affecting the way dogs are able to absorb taurine, thus causing taurine deficiency induced DCM (which is reversible depending on stage, if I understand correctly). They've found this as DCM has been popping up in a bunch of breeds not traditionally diagnosed with DCM, and the common link has been a grain-free diet.
The investigation is still in the early stage. Many cardiologists are recommending dogs be switched to more traditional, grain inclusive diets (or, some approve of appropriately formulated raw diets), providing your dog tolerates grains well (and most dogs do).
Personally, my dogs do just fine on grain. After doing a lot more research into dog nutrition from actual canine nutritionists (rather than self-proclaimed internet experts), I learned so much more about dog food and dog nutrition, and made some different choices about dog food.
This blog has some good posts on nutrition - she is a board certified veterinary nutritionist: https://weethnutrition.wordpress.com/
Richter & Sypha
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