Siberian cat nutrition: slow growth, coat and allergy claims

A Siberian grows slowly and ends up heavy, so feeding one is mostly a matter of supporting a long growth period without letting a large, placid cat get fat. The Cat Fanciers' Association (CFA) calls the Siberian one of the slowest-maturing breeds. Most reach full size by three years, some take as long as five, and mature males weigh 12 to 18 pounds (about 5.4 to 8.2 kg), females 8 to 12 pounds (3.6 to 5.4 kg). The breed's health screening centers on the heart and kidneys.

Calories for a large, slow-growing cat

The Merck Veterinary Manual estimates resting energy requirement (RER) as 70 multiplied by body weight in kilograms raised to the power 0.75. Kittens are fed about 2.5 times RER, neutered adults 1.2 times, intact adults 1.4 times and adults prone to obesity 1.0 times. For adults, rounded to the nearest 5 kcal:

Merck notes that animals of the same weight can differ in need by as much as 30%, so these figures are a starting point. The CFA describes the Siberian as having surprising heft for its size, and the long coat hides both fat and muscle, so body condition has to be judged by hand. The ribs should be easy to feel under a thin layer of fat, there should be a waist behind them, and the belly should not hang or swing when the cat walks.

The long growth period

Nothing published shows whether a slow-maturing breed does better on kitten food for longer, and breeders' advice varies. What matters more than the label is that a young Siberian keeps growing steadily without turning fat. A practical approach:

• Feed a food labeled complete and balanced for growth, or for all life stages, through the first year.
• Weigh the cat every two to four weeks while it is still growing, and score body condition at the same time.
• If a young adult is lean and still filling out, keep portions generous. If it is becoming round, move to an adult food or cut portions, whatever its age.
• Neutering lowers energy needs. Reduce food gradually after the operation and keep weighing.

Protein and fat

Any complete and balanced cat food meets a Siberian's protein, fat and taurine requirements, and there is no breed-specific evidence that it needs more than other cats. Wet, dry or mixed feeding can all work. A larger cat simply eats more of the same food. Choose on what the cat keeps a good body condition on, what its stools and coat look like, and what it will reliably eat. Named animal ingredients at the top of the list are a reasonable preference, but the guaranteed analysis and the complete and balanced statement tell you more.

The coat

The CFA describes the Siberian as a strong, triple-coated cat whose coat is noticeably thicker in the colder months and shorter and less dense in summer. Seasonal shedding is therefore normal. Mats form mostly on the underside, the tail and the "britches" at the back of the hind legs, and the CFA suggests handling those areas several times a week and working any clumps apart with the fingers or a steel comb.

A complete diet already supplies the fatty acids, zinc and biotin a healthy coat needs. Fish oil supplements are sometimes added for dry or itchy skin, but we found no evidence that they change the Siberian's seasonal shedding. A dull, greasy or thinning coat, or matting that suddenly gets worse, can mean the cat is overweight and cannot reach to groom, has arthritis, or has skin disease. That calls for a vet check rather than a supplement.

The hypoallergenic question

Siberians are often sold as low-allergen cats. The evidence is thinner than the marketing. A 2017 study of the genes for Fel d 1, the main cat allergen, noted that the Siberian's reputation for low allergenicity rests largely on breeders' statements. It found gene variants in Siberians that could affect the allergen, and concluded that further research is needed to show whether they reduce it. Anyone with a cat allergy should spend real time with the particular adult cats in a household before committing to a kitten.

Health screening and what it means for food

The CFA lists hypertrophic cardiomyopathy and polycystic kidney disease among the hereditary issues breeders test for, along with several recessive conditions.

Hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) thickens the heart muscle walls and makes the heart less efficient. The Cornell Feline Health Center lists the Siberian among the breeds in which it is more common. Causative mutations are known in Maine Coons and Ragdolls, but a study of eight heart genes in affected cats of several breeds, including Siberians, found no causative mutation, and we found no Siberian-specific DNA test. Echocardiography, an ultrasound scan of the heart, is the screening tool for breeding cats and for any Siberian with a murmur.

We found no evidence that any food or supplement prevents HCM. Every complete cat food contains the taurine a normal heart needs, and extra taurine does not treat HCM. Keeping the cat lean is sensible for a cat that may one day have heart disease. Labored or open-mouth breathing, or sudden pain or weakness in the back legs, is an emergency.

Polycystic kidney disease

Polycystic kidney disease (PKD) causes fluid-filled cysts that slowly replace kidney tissue. Ask whether the parents were screened by DNA test, kidney ultrasound or both. A cat diagnosed with PKD, or with chronic kidney disease from any cause, is usually moved onto a prescription kidney diet chosen by the vet, and those diets restrict phosphorus. Do not start one in a healthy cat. For every Siberian, plenty of water helps: some wet food, fresh water in several places, and a fountain if the cat likes running water.

Pyruvate kinase deficiency

A genetic study of more than 14,000 cats recommended testing Siberians for pyruvate kinase deficiency, an inherited anemia that can cause lethargy, weakness, weight loss and jaundice. It is recessive, so carriers are healthy and testing lets breeders avoid mating two carriers.

Daily feeding routine

• Measured meals, two or three a day, rather than a bowl that is always full. Siberian owners describe the breed as mostly placid, and a placid cat with food always available can put on weight easily.
• Food puzzles for part of the ration give a curious, intelligent cat something to work at.
• Treats kept to about 10% of daily calories and subtracted from meals.
• A monthly weigh-in for adults, since a slow gain of a few hundred grams is invisible under a triple coat.

Sources

1. Siberian. The Cat Fanciers' Association.
2. Nutritional Requirements of Small Animals. Merck Veterinary Manual.
3. Polymorphism Analysis of Ch1 and Ch2 Genes in the Siberian Cat. Veterinary Sciences, 2017.
4. Hypertrophic Cardiomyopathy. Cornell Feline Health Center, Cornell University College of Veterinary Medicine.
5. Analysis of 8 sarcomeric candidate genes for feline hypertrophic cardiomyopathy mutations in cats with hypertrophic cardiomyopathy. Journal of Veterinary Internal Medicine, 2009.
6. Erythrocyte pyruvate kinase deficiency mutation identified in multiple breeds of domestic cats. BMC Veterinary Research, 2012.