It’s a problem many cat owners struggle against: extra pounds. Not on themselves, but on their beloved furry pets. Especially after being neutered, house cats can get lazy — and fat. Most owners switch to special diet or neutered food (hopefully), but that’s not always enough, as often times, cats just eat too much. Now, a new study from the University of Illinois comes to the rescue, explaining just what it takes to help kitty slim down.

In other words, they came up with a cat diet.

“The intent with this diet was a healthy weight loss: getting rid of fat while maintaining lean mass. The big question was how much does it take to make cats lose weight, especially lazy neutered males? It turns out you have to keep reducing their food intake because they’re not very active. It takes a long time,” says Kelly Swanson, a Professor at the Department of Animal Sciences at the University of Illinois.

Keeping a pet on a diet can be more difficult than with a human. It’s not just about the motivation and know-how — there are many more health risks associated with weight loss in pets than in humans. But as long as the change is slow and gradual, things should be ok.

“The risk with rapid weight loss, especially in a cat, is hepatic lipidosis. The body releases too much fat, and the liver gets bogged down. They can’t handle that much,” Swanson says. “We targeted a 1.5 percent body weight loss per week, which falls in line with the range (0.5-2 percent per week) suggested by the American Animal Hospital Association.”

So the first goal is to achieve a 1.5% body weight loss per week, and in order to do this, pet owners should reduce food intake by 20 percent compared to a maintenance diet. But this is only the first step. After that, food intake should be cut bit by bit. Researchers monitored the cats so that their health wasn’t threatened as they successively reduced the food intake. The key to the sustained weight loss was the constant, small reduction of food.

“That’s a key point. When we go on a diet ourselves, we might lose a lot of weight in the first few weeks and then hit a road block. Same with these animals. We had to keep going down, but it can be hard to convince a pet owner to do that. You might get owners to reduce intake from 60 to 50 grams per day, but we’re telling them they might have to go to 45 or 40 grams. We got really low, but we were monitoring them so they were healthy,” he says.

Cats’ weight, like dogs’, is typically assessed on the Body Condition Score (BCS), which rates from 1 to 9. A BCS of 1-3 indicates a less than ideal weight, while a 6-9 BCS indicates an overweight animal. Ideally, pets should have a BCS of 4-5. However, people often tend to underestimate their pets’ BCS. Basically, pet owners tend to ignore their furry friends’ extra pounds. This means that it’s not just the pets, but the humans as well that need to be trained.

“We’ve done some clinical studies in dogs showing that misconception. If you have a veterinarian do a BCS assessment of a pet and then have an owner do it, the owner will almost always underestimate the BCS. Owners need to acknowledge the weight status of their pets.”

“The second thing that needs to change is the owner’s behavior: getting them to reduce food intake to maintain a healthy BCS. Food companies recognize that many owners feed too much, so they’re trying to formulate their diets so it’s easier for the animals to maintain or lose weight even if an owner overfeeds,” Swanson says.

The eight cats in the study were housed together, only going to their individual cages to be fed. Researchers report that their level of activity hasn’t changed significantly over the course of the diet. Researchers emphasize that it’s also important to ensure that your cats are active by playing with them and placing food bowls farther away from favorite resting spots.

Journal Reference: Marissa R. Pallotto et al. Effects of weight loss with a moderate-protein, high-fiber diet on body composition, voluntary physical activity, and fecal microbiota of obese cats. https://doi.org/10.2460/ajvr.79.2.181

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