About 4 months ago, I wrote about a specific type of canine heart disease (dilated cardiomyopathy, DCM) and the recent concern over its association with diet (pet food).
This past week a commentary appeared in a veterinary journal on the subject . It was important to see what is considered expert opinion and have a peek at the results of a survey on this concern, as there’s no doubt it’s a complex issue with serious canine health impacts.
The commentary (quite rightly IMHO) highlights the importance of nutrition and incredible value of obtaining a thorough diet history on all pets as part of a clinic visit. Perhaps as importantly (for me), it also indicates that:
1) there is still an awful lot to learn about nutritional needs-requirements (and how these may vary from dog-to-dog and in dogs of different health states),
2) there is a dearth of peer-reviewed studies, articles or commentaries on canine nutrition, and, 3) there are myriad complexities (and lack of clarity) when it comes to pet food formulation, manufacturing and sales.
The commentary also introduces new terminology (i.e. boutique or exotic diets) to the pet food dialogue. I’m not convinced these terms assist with causation of concern (with respect to cardiac disease or any other). I’d also guess they further cloud a complicated issue (and for me at least, conjure images of fancy French shops) …vs. convey what is (or isn’t) known about these diets and why they may be associated with DCM. The connotation of boutique, i.e. ‘perceived as high-end’, is hard to miss as well….
At present, we simply do not know why (or if) these diets may be linked with canine DCM…and there is much speculation on cause, i.e. low taurine, reduced taurine precursors (i.e. methionine and cysteine), deceased bioavailability, increased (high) fibre preventing enterohepatic binding and recycling, increased taurine loss via the gut and potentially a heightened breed susceptibility…or the association may be naught, i.e. there isn’t one. After all, …a LOT of dogs eat diets containing these ingredients (or ingredients in the speculated proportions), and it appears that the vast majority are unaffected.
Unfortunately, along with the lack of veterinary peer reviewed publications on this subject there has not been disclosure by the FDA on what diets are being investigated… However, I strongly suspect (and really hope!) that plenty of canine diet reformulating (change in diet recipe) has been occurring since this concern was raised, and have my fingers crossed that manufacturers are doing things like:
1) Ensuring all diets have increased taurine (vs. prior levels)
2) Ensuring all diets with significant amounts of water-soluble fibre (peas, lentils, chickpeas, tomato pomace, beet pulp, pea fibre, pea protein) have even higher allotments of taurine (again vs. prior levels)
3) Limiting all new canine diets to 30% legumes (i.e. peas, lentils, chickpeas, pea fibre, tomato pomace)
4) Including additional methionine to try and provide additional precursors for taurine synthesis (if necessary, and vs. prior levels)
The recommendations provided by the commentary similarly provided insight on what we do not know about laboratory sampling and various dietary supplements, e.g. taurine. It’s a tough order to advise the checking of taurine when there is a known lack of consistency in lab standards for analysis, or good understanding of what sample is optimum, i.e. whole blood or plasma. Additionally, it’s hard to feel good about advising taurine supplementation without a standardized supplement and/or optimal dose…
So, what’s a dedicated dog-owner (or DVM) to do? Ask (or keep asking) the tough questions about the diet your dog (or your client’s dog) is eating, be aware of this concern and critically evaluate what information is available, and after a thoughtful dialogue on what makes that dog unique (e.g. risk factors, susceptibilities) and what the diet(s) in question does (or doesn’t) contain…make an informed decision (together) on what is best- for that dog.
We may still have a lot to learn about pet food, K9 heart and overall health & nutrition, but in the meantime, we can work together in a collaborative way to try and keep dogs safe- and maybe even learn more about what they might (or might not) need in the process.