Arginine is an extremely important nutrient in any cat’s diet. Just like taurine, this essential amino acid is found in animal proteins. However, unlike taurine deficiencies which begin to show after months of insufficient nutrition, arginine deficiencies can show up in only hours. Even one meal that lacks arginine can have severe consequences.
Essential Amino Acids
For the benefit of anyone reading this who hasn’t read last week’s post about taurine, let’s do a little recap on what essential amino acids are. Cats’ bodies (and ours) use proteins for rebuilding themselves and for energy. Those proteins are made of little building blocks that go in a very precise order called amino acids. Sometimes the cat’s body can create the amino acids that are needed and sometimes the amino acids must come from the food that is eaten. When the amino acids must come from food, they are called essential amino acids.
Every species has a different number of essential amino acids. Cats have a very unique set of dietary needs because they have 11 essential amino acids: arginine, methionine, histidine, phenylalanine, isoleucine, threonine, leucine, tryptophan, lysine, valine, and taurine.
Ornithine & The Process of Digestion
When your cat eats, the digestive system breaks down the proteins in the food. The amino acids gathered in that process are used to create the proteins and chemicals that the cat’s body needs to function. There are also by-products in this process that are eliminated from the cat’s body. One such by-product for cats is ammonia, a chemical that can be quite toxic in large amounts. The cat’s body uses an amino acid called ornithine to bind to the ammonia molecules and lead them out of the body.
Ornithine is one of the amino acids that can be created by the cat’s body. However, the only way that orthinine can be made by cats is with the essential amino acid arginine. Therefore, arginine must be present in the food the cat eats to avoid ammonia toxicity.
While arginine deficiency is rare, it is a very serious problem. A study done on the effect of a diet lacking arginine on cats concluded ” [Arginine] provides a unique example of a nutrient so critical that one meal without dietary arginine may result in death.” Cats that first fasted overnight were fed a meal that deliberately had no arginine. Within hours of the deficient meal, cat began showing symptoms of ammonia toxicity and high blood sugar. They also experienced rapid weight loss with an average weight loss over 24 hours of 6.8 g (about 0.3 ounces). Sadly one of the cats in the study passed away.
Symptoms of ammonia toxicity include:
- Ataxia (when the cat looses control of it’s body)
Preventing Arginine Deficiency
The good news is that preventing arginine deficiency is pretty easy. It doesn’t take a whole lot of arginine to keep things in balance and almost all meats contain it. If your cat is not exhibiting the symptoms listed above, they are probably getting enough arginine in their current diet. Cats can have problems with arginine levels if they don’t eat for a long enough period of time or if they have liver diseases like hepatic lipidosis.
According the National Research Council, an adult cat needs a minimum daily allowance of 190 mg/kg (about 85 mg/lb). An ounce of raw chicken has about 360 mg of arginine and an ounce of raw beef has about 410 mg of arginine. Other foods that have high arginine levels are turkey, rabbit, seafood. Legumes (like peas) and dairy products can help boost arginine levels as well, but they are somewhat controversial in cat food for other reasons.