The lack thereof a key contributor to Dilated Cardiomyopathy (DCM)
The matter of the broken heart … recent awareness around deaths associated with DCM in dogs has brought into spotlight again the lack of taurine in various forms of commercial and boutique pet feed for cats and dogs. A condition and disease that could have been averted, if the veterinary profession and associated pet food industry would acknowledge that taurine is an essential amino acid in pet food.
Read More: FDA Investigating Potential Connection Between Diet and Cases of Canine Heart Disease (FDA).
However, it is not a clear-cut case *yet* – the BigWhiteLabcoat community still add disclaimers to their research notes and articles .. “It’s not yet clear if diet is causing this issue” … whilst most holistic and integrated veterinarians and others knowledgeable about veterinary nutrition, and who understand the link between diet and disease, imply that they are not surprised. Taurine, which should be an essential amino acid, is found in meat, and as in the case for cats, as meat-eating obligate carnivores, haven’t developed the ability to make their own taurine.
What is Dilated Cardiomyopathy?
Dilated cardiomyopathy (DCM) occurs in cats (and dogs) where it is associated with a nutritional deficiency. DCM is a serious disease of the heart muscle which causes the heart to beat weakly and to enlarge. DCM can result in abnormal heart rhythms, congestive heart failure (a build-up of fluid in the lungs or abdomen), or sudden death. In dogs, it typically occurs in large- and giant-breeds, such as Doberman pinschers, Boxers, Irish Wolfhounds, and Great Danes, where it is thought to have a genetic component. Recently, some veterinary cardiologists have been reporting increased rates of DCM in dogs – in both the typical breeds and in breeds not usually associated with DCM, such as Miniature Schnauzers or French Bulldogs.
Pet Feed or Food?
Because most dogs can make their own taurine from other amino acids, it’s been thought that they didn’t need such supplements. But in the last few years, researchers have discovered that a few dogs evidently can’t supply their own taurine needs! Compound this problem with the fact that there is no minimum requirements for taurine or carnitine (a vitamin-like derivative of an amino acid) in commercial dog feed, plus many common ingredients in dry feed have low digestibility and anti-nutrient effects; further decrease the absorption of the little taurine, carnitine, and other amino acids and nutrients present in these highly processed feeds. High heat processing and extended periods of storage have also been linked to decreased availability and absorption of amino acids.
Recently, grain-free foods that utilize legumes have been put in the spotlight on this issue, because since many of the legume ingredients they use are high in protein, it can artificially increase the protein percent of the food, leading owners to believe that their dogs will be getting the benefits of a high protein diet. However, legumes contains no detectable taurine, and plant-based proteins have low digestibility in comparison to meat-based proteins for dogs.
What Does Taurine Do Inside the Heart?
Over the last few decades, it has become clear that taurine plays a key and integral role in the transport of positively charged calcium ions in the heart. Taurine also plays an equally important role in controlling how sensitive heart cells are to the calcium ions they encounter. In other words, taurine plays a pivotal role in the normal functioning of the electrical system of the heart. In performing this crucial role, taurine can be thought of as the master switch for one of the most fundamental elements of life: the heartbeat!
Without an adequate supply of taurine stored inside each heart cell, the heart will fail to beat properly. This was suspected by many scientists long before it was absolutely proven. Moreover, this is now a well-proven scientific fact. If taurine levels fall too low, heart contractions may become too weak to supply the body with the oxygenated blood it needs to flourish and too weak to remove toxins. It has also been proven that an irregular heartbeat can be induced by reducing taurine and this same irregular heart beat can then be cured by restoring taurine back to normal levels. Further, the outer and inner membranes of each heart cell will deteriorate without proper taurine levels.
Taurine is so important to the normal functioning of the heart, it is stored in great quantities inside a membranous structure called the sarcoplasmic reticulum inside each heart cell. However, the exact mechanisms by which taurine controls the life-giving tasks are not entirely understood yet, even by the scientists actively studying these biochemical reactions. However, this is an area of very active scientific research because taurine supplementation (or increased taurine in diet) is thought to hold great promise in preventing, and even reversing, many heart disorders, diabetes, and other common life-compromising ailments in both pet parents and pets.
How to add additional Taurine to the diet?
Across all animals, there is a direct correlation between how fast the heart beats, i.e. how hard the heart works, and how much taurine will be found in each gram of heart tissue! This is because a faster beating heart needs more taurine than a slower beating heart to function properly. There’s also more taurine in the skeletal muscles of animals with higher heart beat rates. This makes sense because animals that have a higher metabolic rate need a corresponding higher heart rate.
Looking at the heart rates below, you will notice two standouts: rodents and birds! There is so much more taurine in rodent and bird hearts. Birds have an extremely high metabolism, even at rest, and therefore have a heart that beats very fast and is exceptionally high in taurine. Birds also often engage in activities over extended periods that require their hearts beat even higher than a mouse. For example, if you’ve ever watched ducks on the water, you know they can be very energetic beasts! Dabbling or diving for food, diving to escape danger (eagle or human approaching) and taking off in flight from the surface of the water all require a tremendous amount of energy. Duck hearts are designed to handle these intense bursts of energy and their heart rate can skyrocket in mere seconds!
- Mouse: 450–750
- Hamster: 300–600
- Adult Chicken: 250–300
- Chick (baby chicken): 350–450
- Domestic Turkey (Broad Whites): 298-309
- Tufted Duck (a diving duck) Floating On Water: 260
- Common Pochard (a diving duck) Floating On Water: 158
- Cat: 120–140
- Dog: 70–120
- Sheep: 70–80
- Goat: 70–80
- Dairy Cow: 48–84
- Horse: 28–40
- Elephant: 25–35
In 1979, there was a very interesting experiment conducted with two types of diving ducks, the Tufted Ducks and Common Pochards. This experiment clearly illustrated just how fast a duck’s heart rate can escalate when they dive. It also showed that even at rest, ducks have an exceptional high heart rate. Since ducks can double their already exceptionally high resting heart rate within a few seconds, we can logically conclude that they must store plenty of taurine inside their heart tissue to accommodate these herculean feats! This is also why duck skeletal meat is so dark. The darker the poultry skeletal meat, the more taurine it contains. Even slower birds, like chickens and domesticated turkeys, have very high metabolic rates due to their heritage and their continued need to be able to produce a great burst of energy for flight and other activities like escaping eagles and foxes coming into yard!
Relative to their body size, birds also tend to have a larger heart than mammals and they pump out more volume of blood with each beat – bet you didn’t know that!
How You Can Protect Your Fur Kids?
As Dr Karen Becker wrote in her article, titled “Dogs Fed Grain-Free Kibble May Be at Risk for Heart Disease”, “Those of us who are passionate about animal nutrition have been having a painful awakening for some time now about just how nutrient-deficient many dogs and cats are today. The taurine-DCM issue in dogs is yet another example that animals need much higher levels of bioavailable amino acids from a variety of sources than most are consuming.
Read More: Dogs Fed Grain-Free Kibble May Be at Risk for Heart Disease, Dr Becker (Mercola)
Unfortunately, some processed pet food advocates are using the link between grain-free dog foods and DCM to try to push pet parents back in the direction of grain-based diets. Don’t be fooled. The problem with grain-free formulas isn’t the lack of grains! It’s the high level of starchy carbohydrates coupled with the extreme high-heat processing methods used to produce these diets.
Until we have much more information on the subject, my current recommendation is to supplement all dogs with high-taurine foods, no matter what type of diet they’re eating. An easy way to do this is to simply mix a can of sardines into your pet’s meal once a week. You can also find the taurine content of many other foods on page two of this study 1 (PDF) [below] and in this Raw Feeding Community article.”
Read More: Grain free diets and DCM, The Raw Feeding Community (Blog)
- Tuna/canned: 42
- White fish/raw: 151
- Mussels/raw: 655
- Oysters/fresh: 70
- Cod/frozen: 31
- Clams/fresh: 240
- Clams/canned: 152
- Milk and derivatives
- Pasteurized milk: 6
- Cheddar cheese: not detected
- Yogurt/low fat plain: 3.3
- Ice cream/vanilla: 1.9
- Fruit, vegetables, seeds, nuts, grain, beans, peanuts, cereals: not detected
(Taurine content is expressed in mg (mean)/100 g wet weight.)
If you have a breed or breed mix known to be susceptible to DCM (e.g., Golden Retriever, Doberman Pinscher, Cocker Spaniel, Boxer, Great Dane, Scottish Deerhound, Irish Wolfhound, Saint Bernard, Afghan Hound, Dalmatian, Portuguese Water dog, Old English Sheepdog, Newfoundland), especially if you’ve been feeding grain-free kibble, or if for some other reason you’re concerned about your dog’s heart health, Dr Becker recommend following Dr. Joshua Stern’s four-step process outlined in her article, starting with a visit to your veterinarian.
Of course, DCM in some breeds like Dobermans is genetic, so unfortunately there is no guarantee fooding real taurine-loaded food will cure or prevent DCM in every case. But any breed susceptible to DCM can use all the help they can get, and this is just one way to make sure you are providing all the building blocks the body needs for optimal heart health, since it is well documented that kibble alone may not do that.
Fooding raw real food or supplementing the diet with taurine and/or carnitine, could help promote a healthy heart and make up for some of what kibble lacks.
Articles and Videos
Selected References and research.
- Hickman M.A., Rogers Q.R., Morris J.G. Effect of Processing on Fate of Dietary Taurine in Cats. J. Nutrition 1990; 120: 995-1000;
- Nutrient Requirements of Dogs and Cats. Report By the National Research Council. Washington, DC: The National Academies Press, 2006 ;
- Gregory M. Douglass, Edward B. Fern, Androbert C. Brown. Feline Plasma and Whole Blood Taurine Levels as Influenced by Commercial Dry and Canned Diets. 1991; J. Nutr. 121: S179-S180;
- James G Morris, Quinton Ray Rogers, Linda M Pacioretty. Taurine: An Essential Nutrient For Cats. J. Small Anim. Pract. 2008; 31(10):502 – 509.;
- Ko KS, Fascetti AJ, Dietary beet pulp decreases taurine status in dogs fed low protein diet.;
- Kim SW, Morris JG, Rogers QR. Dietary soybean protein decreases plasma taurine in cats.;
- Kim SW, Rogers QR, Morris JG. Maillard reaction products in purified diets induce taurine depletion in cats which is reversed by antibiotics.;
- Mauron J. Influence of processing on protein quality.;
- Pamela A. Williams Suzanne M. Hodgkinson Shane M. Rutherfurd Wouter H. Hendriks. Lysine Content in Canine Diets Can Be Severely Heat Damaged.;
- van Rooijen C, Bosch G, van der Poel AF, Wierenga PA, Alexander L, Hendriks WH. Quantitation of Maillard reaction products in commercially available pet foods.;
- Fascetti AJ, Reed JR, Rogers QR, Backus RC. Taurine deficiency in dogs with dilated cardiomyopathy: 12 cases (1997-2001). ;
- Tôrres CL, Backus RC, Fascetti AJ, Rogers QR. Taurine status in normal dogs fed a commercial diet associated with taurine deficiency and dilated cardiomyopathy.;
- Delaney SJ, Kass PH, Rogers QR, Fascetti AJ. Plasma and whole blood taurine in normal dogs of varying size fed commercially prepared food.;
- Sanderson SL, Gross KL, Ogburn PN, Calvert C, Jacobs G, Lowry SR, Bird KA, Koehler LA, Swanson LL. Effects of dietary fat and L-carnitine on plasma and whole blood taurine concentrations and cardiac function in healthy dogs fed protein-restricted diets.;
- Backus RC, Cohen G, Pion PD, Good KL, Rogers QR, Fascetti AJ. Taurine deficiency in Newfoundlands fed commercially available complete and balanced diets.;
- Backus RC, Ko KS, Fascetti AJ, Kittleson MD, Macdonald KA, Maggs DJ, Berg JR, Rogers QR. Low plasma taurine concentration in Newfoundland dogs is associated with low plasma methionine and cyst(e)ine concentrations and low taurine synthesis.;
- Bélanger MC, Ouellet M, Queney G, Moreau M. Taurine-deficient dilated cardiomyopathy in a family of golden retrievers.;
- Janet Olson, DVM, DACVIM (Cardiology). Taurine Deficiency Induced Dilated Cardiomyopathy in Golden Retrievers.;
- Dr. Jean Hofve, Holistic Veterinarian, The Importance of Taurine for Dogs and Cats. ;
- Thomas H. Maugh II. Thousands of Cat Deaths Traced to Pet Food Deficiency. Los Angeles Times. August 14, 1987. ;
- Pion PD, Kittleson MD, Rogers QR, Morris JG. Myocardial Failure In Cats Associated With Low Plasma Taurine: A Reversible Cardiomyopathy. Science 1987; Aug 14;237(4816):764-8. ;
- Resting Heart Rates Merck Veterinary Manual. Online Edition Revised March 2012. ;
- L. M. Krista, Ray E. Burger and P. E. Waibel. Blood Pressure and Heart Rate in the Turkey as Measured by the Indirect Method and their Modifications by Pharmacological Agents. Poultry Science (1963) 42 (3): 646-652.
- P. J. Butler AND A. J. Woakes. Changes In Heart Rate and Respiratory Frequency During Natural Behavior of Ducks, With Particular Reference To Diving. J Exp Biol 79, 283-300. ;
- Harris Ripps and Wen Shen. Review: Taurine: A “Very Essential” Amino Acid. Mol Vis. 2012; 18: 2673–2686. ;
- Stephen W Schaffer, Chian Ju Jong, Ramila KC, and Junichi Azuma. Physiological Roles Of Taurine In Heart and Muscle. J Biomed Sci. 2010; 17(Suppl 1): S2. ;