American Shorthair nutrition: portions, heart and teeth

The American Shorthair has few breed-specific health problems, so its diet is mostly about portion size. According to the Cat Fanciers' Association (CFA), the breed descends from shorthaired cats that came to North America on settlers' ships to control rodents, and it is not currently known for any breed-specific health problems. It is a medium to large, muscular cat with a dense coat, affectionate but independent enough to amuse itself. A calm indoor cat of that build can put on weight steadily without looking much different, which is why measured feeding matters more than any special ingredient.

Why weight matters

There is no good evidence that American Shorthairs gain weight more easily than other breeds. Neutering, indoor life and food that is always available are the main risks for any cat. What is well established is the cost of excess weight. In a US study that followed nearly 1,500 cats for four and a half years, obese cats were 3.9 times as likely to develop diabetes, 4.9 times as likely to need veterinary care for lameness and 2.3 times as likely to develop non-allergic skin problems as cats of optimal weight.

Overweight cats also face a specific danger when they stop eating. The Cornell Feline Health Center explains that when a cat goes without food, fat moves from body stores to the liver faster than the liver can process it. This condition, hepatic lipidosis or fatty liver, appears to be much more common in obese cats and is likely to be fatal without prompt treatment. An overweight cat that has not eaten for a day or more needs a vet, and weight loss plans for cats should be gradual and supervised rather than based on cutting food sharply.

Daily calories for indoor cats

The Merck Veterinary Manual estimates a cat's resting energy requirement as 70 × body weight in kg to the power 0.75. It multiplies that by 1.2 for a neutered adult, 1.4 for an intact adult and 1.0 for a cat prone to obesity, and by 2.5 for kittens. For an adult at its ideal weight, the figures work out as follows.

Treat these as starting points and adjust to body condition. Weigh the cat monthly, and feel for the ribs: at a healthy weight they are easy to find under a thin layer of fat, with a visible waist from above. The dense coat can hide a thickening middle.

Weigh food rather than scooping it. Scoops are less accurate than most people assume. When dog owners in one study measured out dry food with cups and scoops, their portions ranged from about 48 percent too little to 152 percent too much. The same problem applies to kibble for cats, and at a cat's small daily ration a few extra grams add up. A kitchen scale that reads in single grams costs little. Free-feeding suits few indoor cats; two or more measured meals, or a measured daily amount split into puzzle feeders, works better.

After neutering

Neutering lowers energy needs. In a study of young cats fed to maintain an ideal body condition, the energy needed after neutering fell by an average of 17.6 percent in males and females combined. A workable routine is to reduce the portion from the time of surgery rather than waiting for weight gain, and to weigh the cat every two to four weeks for the next six months so portions can be adjusted before the gain becomes hard to reverse.

Heart disease and taurine

Hypertrophic cardiomyopathy (HCM) thickens the heart muscle and is the most common heart disease in cats. The Cornell Feline Health Center includes the American Shorthair in its list of breeds predisposed to HCM, alongside the Maine Coon, Ragdoll and British Shorthair. The CFA reports that HCM appeared in some American Shorthairs in the 1980s and 1990s and has largely disappeared from the breed through testing and selective breeding. Both can be true. The risk in well-bred lines may now be low, but a cat of unknown background has no such history behind it.

Many cats with HCM show no signs. Others breathe fast or with an open mouth, or become lethargic. A blood clot that suddenly paralyzes the hind legs is an emergency. A heart murmur or a raised resting breathing rate should lead to an echocardiogram, and breeders can be asked whether their cats have been screened.

No diet prevents or treats HCM. Taurine matters for a different reason. Cats cannot make enough of it, and Merck notes that a deficiency causes dilated cardiomyopathy and retinal degeneration. Complete commercial cat foods contain enough. A home-cooked diet needs a recipe formulated by a veterinary nutritionist, because taurine is one of several nutrients that are easy to get wrong. Cats already diagnosed with heart disease may need changes to sodium or other nutrients, and those should come from the vet managing the case.

Teeth

Dental disease is common in cats of every breed, and American Shorthairs are no exception as they age. Brushing with a cat toothpaste, started while the cat is young, is the most effective home care. Dental diets and treats accepted by the Veterinary Oral Health Council can help alongside brushing, but ordinary dry food is not a substitute for either. Bad breath, drooling, dropping food, chewing on one side or pawing at the mouth need a veterinary check, and older cats often need dental treatment under anesthesia.

A balanced diet

Feeding a healthy American Shorthair does not need to be complicated. Choose a food labeled complete and balanced for the cat's life stage. Merck cites a minimum of 26 percent protein on a dry matter basis for adult cat foods under AAFCO profiles, and most commercial foods exceed that. Beyond the minimums, the calorie content per cup, can or 100 g is the number most worth reading, since that decides portion size.

• Wet and dry food. Both can be complete. Wet food adds water, which helps cats that drink little and is often advised for cats with a history of urinary problems.
• Treats. Keep them to a small share of daily calories and subtract them from meals.
• Activity. Two or three short play sessions a day with a wand toy use energy and keep an indoor cat engaged. The guide to indoor cat activity has ideas.

Sources

1. American Shorthair. The Cat Fanciers' Association.
2. Associations between body condition and disease in cats. Journal of the American Veterinary Medical Association, 1998.
3. Hepatic lipidosis. Cornell Feline Health Center.
4. Nutritional requirements of small animals. Merck Veterinary Manual.
5. Dog owner's accuracy measuring different volumes of dry dog food using three different measuring devices. Veterinary Record, 2019.
6. Growth curve and energy intake in male and female cats. Topics in Companion Animal Medicine, 2021.
7. Hypertrophic cardiomyopathy. Cornell Feline Health Center.