The following is a summary of a webinar featuring 3 experts in the field of veterinary nutrition and updating us on the current DCM issue seen in dogs and cats on certain diets released September 8, 2018.
FDA representative (Dr. Martine Hartogenesis-Deputy Director, FDA Center for Veterinary Medicine):
Veterinary cardiologists approached the FDA in July, 2018 with cases of DCM in dogs eating certain legume (lentils, chickpeas) and tuber (potato) based diets. FDA is currently tracking 150 cases-145 dogs (39 deaths) and 5 cats (l death) with 90% of those with a history of consuming grain free diets with legumes or tubers. The FDA has not reached out to individual pet food companies (“would take too much time”) but to the Pet Food Institute (PFI) of which 90% of pet food manufacturers belong to about these cases. Interestingly, smaller, “boutique” pet food companies may not belong to PFI so they are not being contacted by any regulatory agency to validate their ingredients/formulation. The FDA was asked if the source of taurine in the diet was being investigated and their answer was that they are deferring that to individual pet food companies.
Pet food nutrition expert (Dr. Lisa Freeman-PhD, Diplomate American College of Veterinary Nutrition and professor at Tufts University College of Veterinary Medicine):
DCM is a reduced contractility of the heart muscle resulting in thinning of the walls of the heart causing the heart to not pump blood adequately resulting in an abnormal rhythm. Symptoms include fainting and sudden death. Taurine is an amino acid made from methionine and cysteine and is needed for a strong heart muscle. She feels these cases are not just a taurine deficiency as the majority of cases measured were not taurine deficient. There are 3 types of taurine related DCM: the first are genetically predisposed breeds to DCM-Doberman pinschers, Newfoundlands. Second is taurine deficiency in typical and atypical breeds such as Cocker spaniels, Golden retrievers, Miniature schnauzers. Third is diet associated taurine deficiency DCM that were eating diets adequate in taurine (an absorption or excretion problem in those dogs). The majority of cases reported were not taurine deficient and that has nutritionists focused on amino acid sources and bioavailability of methionine, cysteine, and taurine absorption/excretion and their relationships to each other.
Pet food formulation specialist (Dr. Greg Aldrich-PhD, Associate research professor at Kansas State University and president of Pet Food & Ingredient Technology, Inc.):
Legumes provide about 50% absorption of amino acids such as methionine (meat provides higher levels). Potatoes are not a contributor of amino acids or protein in the diet. Some feel that supplementing taurine will rectify the issue but it may mask other issues that are occurring with methionine and cysteine. There has been 50 years of research using corn, wheat, and soy in pet foods but very little research with peas and lentils when used in pet foods. With the emergence of 4000 new pet food products in the last year, small companies are looking for unique ways to capture marketing including incorporating human diet trends into pet foods when no research of those ingredients in pets have been performed.
So the overall summary is that all 3 experts feel there is more than just a taurine issue going on here-it appears to be a formulation problem with amino acids (methionine, cysteine, taurine) and the emergence of small boutique pet food companies vying for a spot in the market using little researched ingredients may have added to the problem.
I talk to a lot of pet owners who criticize large pet food companies but in reality, they are the ones doing the most research in veterinary nutrition and are subjected to more scrutiny by AAFCO and FDA. Next time you think you may know about pet nutrition consider this: dogs and cats are not small humans-they have different nutrition requirements. Does the pet food company you’re using employ a board certified veterinary nutritionist or is it just “veterinarian approved”?–meaningless! Ask to read independent research they have published on veterinary nutrition-bet they haven’t any! ASK, ASK, ASK!!
Addendum 9/19/2019: “FDA searching for possible links between canine diets, heart disease” JAVMA October 1, 2019, pp758-9. Studies done by the FDA indicate that blood taurine concentrations were not predictors of DCM, as dozens of dogs with DCM had normal or high taurine concentrations. The potential connection between diet and DCM could be associated with low bioavailability of taurine or the precursor amino acids dogs use in making taurine or with increased loss of taurine during digestion. So the jury is still out on what is going on with DCM and diet! I’ll keep you posted-Dr. Jeromin
As of October 19, 2023:
Although the FDA investigation caused upheaval in the pet food industry, scientists and others involved with the pet food industry have pointed out the lack of direct evidence connecting those grain-free dog foods to DCM, since the first FDA announcement. Likewise, some have criticized the FDA for going public with the investigation before solid evidence existed, especially considering the negative economic consequences for dog food brands.