Much like their giant cousins in the jungle, your little house cat is a carnivore.
Dogs and cats are both carnivores, which means both species evolved as predators that caught and consumed meat. Considerable research has been done concerning dogs' dietary needs but not nearly as much for cats. Thankfully, however, things are catching up and we're learning more about what our cats need.
Cats are Obligate Carnivores
Obligate carnivores have a shorter and more acidic digestive tract than others. This digestive system more easily digests meat and fat. Obligate carnivores rely on meat to supply the vast majority of their needed nutrients. Whereas some carnivores can survive (not always thrive, but survive) with plant based proteins, cats will gain more nutrients from meat. However, that doesn't mean cats should eat only meat; that isn't healthy either. Although opinions vary, most experts recommend that cats 40% to 50% of a healthy adult cat's diet should be protein with most of that protein coming from meat.
Cats Require Taurine
Many cat owners know that cats require taurine as it made the news when cats were going blind and suffering from heart failure at alarming rates. It was discovered that a deficiency of taurine in commercial cat foods was the cause. Taurine, an essential amino acid, can be found in meat and fish. In addition, cat food manufacturers now supplement their foods with taurine.
Fatty Acids are Essential
Fats are necessary for many of the body's functions, including providing the body with energy and the absorption of fat soluble vitamins. Not just any fat will do, however. Unlike dogs, cats need a food source that supplies both of the fatty acids linoleic acid and arachidonic acid. Although there are many sources for these, poultry is one of the most popular that cats normally eat.
Thiamine is a B Vitamin
Although cats are obligate carnivores and rely on meat for most of their nutritional needs, an all meat diet can cause problems, too. Thiamine, a B vitamin, is an essential nutrient found in plants—most commonly in cereal grains. Cats need as much as five times more thiamine than dogs do and without it can potentially develop a number of problems, including a head tilt, incoordination, a hunched posture, seizures, and even death. Commercial cat foods contain enough carbohydrates and/or vitamin supplements to supply your cat's thiamine needs.
Many cat owners prefer to feed a homemade diet rather than rely on a commercial food. This is fine and these cats can thrive. Because cats do have some unique nutritional needs, before beginning a homemade diet talk to a veterinary nutritionist for guidelines for creating a nutritionally sound diet.
Cats should not Fast
In the wild many predators fast on a regular basis; they gorge when they have food and fast between hunts. Domestic dogs can fast for a day without coming to harm and in fact some dogs will voluntarily skip a meal now and then. With domestic cats, especially overweight ones, fasting can be a serious problem as fasting cats can develop hepatic lipidosis, a serious and even fatal liver disease. Normally when an animal is fasting, the body moves fat from its reserves to the liver to be converted to energy. A cat's body is not designed to process large amounts of fat and the liver quickly becomes overwhelmed and fails. If your cat stops eating call your veterinarian right away.
Cats have unique nutritional needs but that doesn't mean feeding your cat has to be difficult. Just remember cats need to eat a food or a diet designed specifically for them. Don't feed your cat dog food or allow it to eat dog food. Although dog food doesn't contain anything that would make your cat sick, it does lack several things your cat needs.
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