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No Bull, Taurine Is a Must for Kitty
- Updated: Sunday, June 02, 2019 02:37 PM
- Published: Saturday, December 13, 2014 09:21 PM
- Written by Marta Kaspar
I am sure that you have all heard about the importance of taurine for cats. It is a naturally-occurring amino acid mostly found in muscle meat and organs like heart, kidney and liver and in seafood. In muscles, it gets more concentrated the harder the muscle works. Dark meat has more than light meat because it comes from parts of the body that work harder, legs as opposed to breast. Heart is another great example. Although it is termed an organ, it is really the hardest working muscle in the body and has one of the highest concentrations of taurine. Shellfish such as mussels and clams also have a lot of taurine. They are constantly filtering and follow the same "hard-working" scenario, concentrating it to a high degree in their tissues. Small amounts of it are found in dairy products. Plant products contain either low or undetectable amounts it. Despite meat being a good source of taurine, there is a significant amount of variability within meat samples according to a published study.¹ Taurine content of meat was not only affected by diet, breed and environment, but also by the freshness of the meat.
Cats are obligate carnivores. Unlike herbivores or omnivores, they are not able to synthesize the taurine they need from other amino acids like methionine and cysteine. In addition, many animal species can use glycine or taurine to conjugate bile acids into bile salts, but cats can only conjugate bile acids with it. This low rate of synthesis combined with the loss of it in bile contributes to an increased dietary requirement of taurine for cats. With insufficient amounts of this essential amino acid in their diet, cats can develop central retinal degeneration, reproductive failure and impaired fetal development or heart cardiomyopathy. Clinical signs of deficiency will not be apparent right away. It might take a couple of months or years in some cases, but once a cat starts exhibiting clinical signs, significant damage has already been done.
One very important property of taurine is its high solubility in water. The final amount of it in the food will depend on the food preparation and storage techniques. To minimize the loss, one should always try to retain all of the liquids coming from the meat. For example, if the meat is cooked, it should be done in a small amount of water so that it can all be incorporated back into the food. Cooking meat at temperatures used for normal food preparation by itself does not change the amino acid in any way. It just leeches it out from the meat into the water. I have been asked many times if it loses its potency during food storage in the freezer. The answer is yes and no. Freezing does not affect taurine potency, but, during the thawing process, a lot of liquid is released. Since it is highly water soluble, that liquid will be taking a lot of the meat's taurine with it. For example, if you buy raw ground meat/bone/organ packages, the liquid that comes out as it thaws – which is not blood despite its red color – is full of dissolved taurine. If this broth is discarded, the meat ends up with a lower amount than before freezing.
The Association of American Feed Control Officials, or AAFCO, recommends the minimum allowance of taurine for wet food to be 0.2% on a dry matter basis. The chance is that this amount might be covered by the natural taurine in meat alone, but due to a significant amount of variability of its concentrations in meat, high solubility in water, danger of delay in exhibiting clinical signs of deficiency and the fact that supplementation is relatively safe with no reports of any issues associated with overdose, it might be beneficial to always have a small amount of excess in your raw cat food. So what would be a reasonable amount to add? It is approximately 250 mg of taurine per 1lb of meat. I intentionally use "mg" because all supplements are sold as "mg per capsule." Since the smallest amount available is 500 mg per capsule, you can either add one of these capsules to two pounds of meat or 1/2 capsule per one pound of meat.
A lot of you might not like the fact that supplemental taurine is always synthetic. While I would also prefer a natural product over synthetic, in this case unfortunately, there is currently no other choice. It is important to keep in mind, however, that chemically there is no difference between synthetic or natural because both structures are exactly the same. Taurine, unlike many other amino acids, does not polarize light so there is no left or right rotation which can differentiate natural or synthetic types. Some companies use this exact reasoning to justify their claim as natural, but I can assure you that it is only a marketing strategy. It can be extracted from natural sources – there is a company in New Zealand that extracts it from ox bile – but this method is commercially unappealing and significantly more expensive. Nevertheless, I am hopeful that one day, a truly natural taurine will be available to benefit cat nutrition.
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Marta Kaspar holds a master's degree in chemistry from the University of Pardubice in the Czech Republic. She is a research scientist, and a formulation and analytical chemist in both industrial and academic fields. Marta became interested in feline nutrition when her cats developed health problems. When she decided to prepare their food herself, the effect of the homemade raw meat diet on her cats was so impressive that she created the line of Alnutrin® supplements to help others transition their cats to better diets. You can find her atknowwhatyoufeed.com.
1. AR Spitze, DL Wong, QR Rogers and AJ Fascett, "Taurine Concentrations in Animal Feed Ingredients; Cooking Influences Taurine Content," Journal of Animal Physiology and Animal Nutrition 87, 2003, 251-262.