What is Taurine?
Taurine is an essential amino acid for cat (more precisely, it’s a beta-amino sulfonic acid). Unlike dogs, cats cannot synthesize taurine within their bodies, so it must be included in their diet. Taurine is mainly found in dark meat and muscle by-products, although it is present in light meat to some extent. The richest sources of taurine are found in small animals, for example, mouse meat contains the maximum amount of taurine (nature took care of cats here!).
The Importance of Taurine for Cats
Taurine deficiency can lead to central retinal degeneration and blindness in cats, cardiomyopathy, and heart failure, which can result in the death of the cat, as well as other disorders such as inadequate immune response, poor growth of newborns, poor reproduction, congenital fetal defects, and much more. Excess taurine is not toxic as it is excreted in the urine.
So, why argue about it? It seems simple: just give taurine as a supplement to all cats that don’t eat mice! After all, excess is easily excreted, it’s practically impossible to exceed the dosage to toxic levels, and without it, all cats will start getting sick and dying. But there are people who are against adding taurine to the diet! They argue that if a cat is on a natural diet, it gets the required amount of taurine from meat! But is that true?
Debate on Taurine Supplementation
At the dawn of commercial pet food consumption, manufacturers did not add taurine to the food, and cats consuming this food began to get sick and die. It was at that moment that active research on the effects of taurine on cats’ bodies began. After conducting these studies, taurine began to be added to all commercial pet foods.
How Much Taurine Does a Cat Need?
There is no universal answer regarding the amount of taurine needed, as it depends on the cat’s diet. Domestic cats can have very different diets, and the composition of the diet directly affects the amount of taurine in the diet and its bioavailability.
The recommended norm, as defined by the NRC (National Research Council of the National Academies of the United States):
- For dry foods, the NRC recommends 250 mg per 1000 kcal.
- For wet products, such as canned food, the NRC recommends 425 mg per 1000 kcal.
This difference is due to the bioavailability of taurine in different diets.
In fact, some elements of the diet can reduce the availability of taurine. These elements mainly include fiber and certain types of proteins. The degree of thermal processing of the diet also plays a role. In particular, some fibers, such as rice bran, can bind to taurine in the small intestine. Certain protein compounds can also bind to taurine, making it unavailable to the cat.
Regarding thermal processing, cooking certain proteins leads to the formation of Maillard products, which promote the growth of certain types of bacteria. These bacteria degrade taurine and make it unavailable to cats again. Canned foods contain more Maillard products, which explains why they have the highest taurine requirement. Similarly, dry food also contains Maillard products and a high fiber content, which reduces the bioavailability of taurine.
Taurine in Raw Diets and Home-Prepared Meals
For a raw diet, it’s still more complicated because there is no official recommended dose of taurine. This means we cannot precisely calculate how much taurine is present in certain meats after they’ve been purchased from the store. Of course, if you feed your cat homegrown chickens and rabbits, you can use different resources. There are tables with approximate taurine content in various types of meat. These tables can help you estimate the taurine levels in the meat you provide.
Based on the results of several studies, it was recommended to use the same norms as for dry food because raw meat also contains bacteria that can degrade taurine. This leads us to the recommendation of 250 mg per 1000 kcal.
You can determine whether to add taurine to your cat’s diet with dry or wet food by taking data from the food packaging and comparing it with the recommended values. If the taurine in your food is less, then it should be added.
Myths and Debates about Taurine: is it Necessary to Add Taurine to Homemade Food?
Contrary to popular belief, taurine is not destroyed during meat preparation. However, taurine is water-soluble. Therefore, during any kind of processing (including cooking), some amount of taurine may be lost. If meat is cooked in water (boiled or steamed), it will lose more taurine than if it were baked. However, despite the fact that cooked meat still contains some amount of taurine, the bioavailability of taurine will be reduced in the presence of Maillard products obtained during thermal processing.
Similarly, when thawing frozen meat, some amount of water is released: in this water, called myoglobin, some taurine is lost.
Finally, when meat is ground, there is also some loss of water. Additionally, grinding also increases exposure to air, in which bacteria thrive (and, as we now know, taurine is susceptible to bacterial degradation). Meat from mechanical deboning also contains particularly low levels of taurine, probably because it is low-quality meat and processed.
This means that all claims that store-bought meat, which we give to cats, contains enough taurine are unfounded. We cannot know how much taurine is contained in a piece of beef if that piece comes from an unknown source, has been mechanically deboned, and especially if it has been ground. Often, we don’t even know if we are buying fresh meat or if the product has already been frozen.
Should You Supplement Taurine?
Many owners freeze raw products before feeding them to their cats to destroy parasites in the meat, which in turn further reduces the taurine content in the meat. If the diet contains fiber, it will also reduce the bioavailability of taurine.
For example, a piece of beef heart purchased from the store in a frozen state may contain only 20% of the taurine from its initial value immediately after the slaughter of the cattle – 582 mg per 1000 kcal. In this case, we would get levels much lower than the recommended norm for cats.
So, by all accounts, it’s better to add taurine to the natural diet of cats. At least the minimum daily dose should be added for a raw diet. For a processed diet with fiber, the full daily dose of taurine is recommended. It’s also necessary to add taurine when feeding commercial foods. This is important if the taurine content in the food does not meet the recommended standards.
You can calculate the calorie content of your cat’s diet and the daily dose of taurine for natural feeding yourself. For those who are too lazy to calculate, I will provide the generally accepted minimum daily doses from a veterinary dietitian. On average, for an adult cat weighing up to 5 kg, the taurine supplement should be at least 30 mg per day, and for kittens weighing up to 3 kg, the taurine supplement should be at least 60 mg per day.
Where to Get Taurine?
You can purchase taurine specifically for cats at a pet store or at a human pharmacy. It’s best to purchase a monopreparation rather than taking multivitamins with taurine, as the other vitamins may not be necessary or even harmful to your cat. For example, readily available today may be the drug Dibicor or dietary supplements containing taurine for oral intake. You can crush the tablet and add the necessary amount to food or administer it in a gelatin capsule, which can be purchased separately.
This article is not a recommendation from a dietitian. It simply provides an overview of recent research on taurine in the diet of cats. If you are unsure about the composition of your cat’s diet, it is ideal to seek advice. You should consult a qualified veterinary dietitian.