Tonkinese cat nutrition: diabetes, weight and bladder stones

The health risk in a Tonkinese that food affects most directly is diabetes. In a study of more than 190,000 cats seen by English vets, Tonkinese had about four times the odds of diabetes compared with crossbred cats, and odds rose for cats of any breed as body weight climbed above 4 kg. Keeping a Tonkinese lean is therefore the main job of its diet. A few inherited conditions from the breed's Burmese and Siamese ancestry add some specific things to watch.

Where the breed comes from

According to the Cat Fanciers' Association (CFA), most Tonkinese descend from one cat, Wong Mau, a small walnut-brown female brought to America in 1930 who was also the foundation of the Burmese breed. Bred to a Siamese, she produced kittens of three types; the solid brown ones founded the Burmese, and those that looked like her were used for Tonkinese. The breed was recognized in Canada in 1960 and by the CFA in 1982. The CFA describes a medium-sized, muscular cat that feels heavy for its size, intelligent, outgoing and vocal.

Diabetes risk and body weight

The English study used records from 118 primary-care practices in the VetCompass program. About 1 in 200 cats had diabetes. After accounting for other factors, Tonkinese had odds of diabetes 4.1 times those of crossbred cats (95% confidence interval 1.8 to 9.6). Norwegian Forest Cats (3.5) and Burmese (3.0) also had raised odds. Across all cats, odds rose with each body weight category above 4 kg and with age beyond 6 years. The authors took the breed pattern as support for a genetic predisposition.

Genes cannot be changed; body weight can. In practice:

• Feed measured meals rather than leaving a bowl topped up all day.
• Weigh the cat every month or two and act on a steady gain before it becomes obesity.
• Judge condition by feel: ribs easy to feel under a thin layer of fat, a visible waist from above.
• See a vet if the cat drinks or urinates more than usual, or loses weight while eating well.

Carbohydrate content gets a lot of attention, but evidence that a low-carbohydrate food prevents diabetes in a healthy cat of normal weight is limited. For a lean Tonkinese, the calorie total matters more than the carbohydrate percentage. A cat that is already diabetic needs a diet chosen with the vet as part of its treatment.

How much to feed

The Merck Veterinary Manual estimates a cat's resting energy requirement as 70 × body weight in kg to the power 0.75, then multiplies it by 1.2 for a neutered adult, 1.4 for an intact adult and 1.0 for a cat prone to weight gain. It gives the minimum protein for adult cat food as 26% of dry matter. The table uses ideal weight.

An active young Tonkinese may need the higher end; a neutered indoor adult usually needs the lower. Treats come out of the total. Puzzle feeders and scattering part of the dry ration give this busy cat something to do and slow down fast eaters, and they work best when the food comes from the measured daily amount.

Hypokalemic polymyopathy

This inherited muscle disease comes from the Burmese side. Affected cats have low blood potassium, and a 2015 review describes muscle weakness and muscle pain usually starting in the first year of life. A characteristic sign is the head and neck bent down toward the chest, although not every cat shows it. Weakness usually comes and goes, and the review notes that signs often waxed and waned, possibly in response to changes in diet and stress.

The cause is a single mutation in a gene called WNK4, which appears to make the kidneys lose potassium. An inexpensive DNA test identifies affected cats and carriers, and the review names the Tonkinese among breeds with Burmese lines from which the condition could be eliminated. A Tonkinese kitten that seems weak, reluctant to walk or unable to hold its head up should be seen by a vet and have its potassium checked. Treatment belongs to the vet; do not add potassium supplements at home.

Calcium oxalate bladder stones

In more than 21,000 feline bladder stones analyzed at the Canadian Veterinary Urolith Centre, Tonkinese were significantly associated with calcium oxalate stones compared with domestic shorthairs, as were Burmese, Siamese and several other breeds. Encouraging water intake, for example with some wet food, is a common part of prevention. Straining in the litter box, blood in the urine or frequent small trips need a vet visit, and a male cat that strains and passes nothing is an emergency.

Amyloidosis from the Siamese side

Familial amyloidosis, in which an abnormal protein called amyloid builds up in organs, is well described in Siamese and Oriental Shorthair cats. In a 2020 analysis of affected Oriental Shorthairs, deposits were mainly in the liver and thyroid, signs usually appeared between 1 and 7 years of age, and the enlarged, fragile liver could rupture and bleed. Published data on how often it occurs in Tonkinese are lacking. No diet is known to prevent it. Sudden weakness, pale gums or a swollen abdomen in a young adult cat of Siamese descent need urgent veterinary attention.

Teeth and gums

The CFA considers the Tonkinese a genetically diverse, generally healthy breed and names only one breed-specific health concern: a tendency toward gingivitis in older cats. Its suggested answer is to get the cat used to tooth brushing while young. Brushing with a cat toothpaste is the most useful habit, and dental diets or treats can help alongside it. Red gums, bad breath, drooling or chewing on one side need a dental check.

Sources

1. Tonkinese. The Cat Fanciers' Association.
2. Epidemiology of diabetes mellitus among 193,435 cats attending primary-care veterinary practices in England. Journal of Veterinary Internal Medicine, 2016.
3. Nutritional requirements of small animals. Merck Veterinary Manual.
4. Periodic hypokalaemic polymyopathy in Burmese and closely related cats: a review including the latest genetic data. Journal of Feline Medicine and Surgery, 2015.
5. Evaluation of 21 426 feline bladder urolith submissions to the Canadian Veterinary Urolith Centre (1998-2014). The Canadian Veterinary Journal, 2016.
6. Complex segregation analysis of familial amyloidosis in Oriental shorthair cats. The Veterinary Journal, 2020.