F1 & F2 Savannah kittens - photo by Michael @ PoC
The cat is the only species that can suffer from taurine deficiency. This is because of the cat’s high “metabolic demand for taurine” and its ability to only synthesise small amounts of taurine. The cat also has a requirement to resupply taurine for losses in faeces due to “incomplete recovery of bile salts…lost in feces”. This is particularly the case with canned cat food (see below for more on this).
Taurine is an organic acid. It is a major constituent of bile and can be found in the lower intestine and, in small amounts, in the tissues of many animals, including humans1. Two of the terms in this definition are explained below:
An organic acid is a compound that contains carbon and which acts like an acid i.e. it has acidic properties. Bile is produced by the liver and is a bitter yellowish liquid. It is necessary for “many aspects of metabolism”. For example, it helps the digestion of lipids in the small intestine. Lipids include fats and fat soluble vitamins. It plays a role in the function of the retina of the eyes and the myocardium of the heart. The myocardium is the middle and thickest layer of the heart wall, composed of cardiac muscle.
Taurine is an essential nutrient that is synthesised by most animals. The word “synthesised” means to combine or produce a substance by the combination of parts or elements to form a whole. Taurine is synthesised from two amino acids, methionine and cysteine. Together with cysteine, methionine is one of two sulfur-containing proteinogenic amino acids1. However cats can only synthesise (create for themselves) small amounts of taurine. Therefore their diet requires a supply of it. The inability of cats to synthesise only small amounts of taurine is due to the low activity of two essential enzymes and the fact that cysteine is diverted away from taurine synthesis.
Apparently, humans also have low levels of taurine synthesis. Taurine is present in animal tissue. High concentrations are found in meat, poultry and fish.
Canned cat food contains a higher percentage of added taurine than dry cat foods. In the USA the minimum levels are:
- canned – 2,000 mg/kg
- dry – 1,000 mg/kg
This is because heat processing of canned foods can damage protein producing by-products that are indigestible. Also the by-products lead to the degradation of taurine. This in turn leads to greater faecal loss of taurine when a cat eats canned food. Please note that this information is good as at 20031. Things change as science learns more.
Taurine deficiency in cats be a serious matter. I cover the subject on this page: Taurine Deficiency in Cats.
Cat Taurine - Notes:
2. The core information for this article comes from Linda P. Case’s fine book: The Cat: Its Behavior, Nutrition and Health published by Blackwell Publishing IBSN 978-0-8138-0331-9