Rabbit obesity rates are on the rise. (Image credit: Getty Images/Fotosearch RF)

Pet bunnies better hop to it. A new study in the British Journal, Veterinary Record notes that, like their owners, their waistlines are expanding at an alarming rate.

The review charted the weight of 41 rabbits over a two-year period and found that about 10 percent of them had packed on so many pounds, they needed to seriously consider salads. Females were twice as likely as males to be portly, and neutered individuals of both sexes were 5.4 times more likely to be overweight compared to their virile counterparts.

OK, maybe the statistics on bunny fatness aren't quite as "hare raising" as they are for humans, but they are climbing. In general rising obesity rates in our animal friends is a well established fact. For example, an annual Association for Pet Obesity Prevention survey of more than 500 pets revealed that approximately 53 percent of cats and 55 percent of dogs are now overweight or obese. The fact that such an organization exists speaks volumes.

Vets say they are seeing increased obesity in their patients of all species.

"Animals used to have to work hard for a living," said Dr. Marty Becker, a veterinarian at the North Idaho Animal Hospital in Sandpoint, Idaho. "Now cats have gone from mousers to moochers. Dogs have gone from guard to lard."

Besides getting their pets' tails off the couch or out of the hutch, Becker advised owners to help their pets practice the art of portion control. He pointed out that a lot of pet lovers equate food with love, constantly stuffing their fur-and-feathered companions with high-fat snacks and super-sized meals.

"Pets are happy to eat whenever and whatever you give them and when you give them free choice they will eat themselves into the grave," he said.

Often, owners don't even realize there's a problem. Becker said that when asked to gauge their pet's body size, most owners rate them as ideal even when they obviously sport too much blubber.

As for bunnies, Becker says a far greater percentage of them than the study reported seem to be trading in their carrots for carrot cake and consequently are tipping the scales too far.

"Some of them have so much skin and fat they remind me of a bean bag chair. You can't even figure out where everything is on them," he said.

Unlike other kinds of animals, it's not always easy to tell if your rabbit is roly-poly. According to Becker, they should resemble an hourglass from the top and have a "wasp waist" from the side. Like other species, they should have just a hint of fat covering their ribs. But this doesn't hold true for all breeds of rabbits.

"An annual checkup is the best way to tell if your rabbit is at its ideal weight," Becker said.

And while corpulent cottontails may be hilarious in cartoons, Becker warned that in real life they're like little tubby time bombs, their health ticking away with obesity-related diseases.

Don't expect them to skip "Hoppy Hour" on their own either. As Becker notes, "It's not like they're staring down bikini season or desperately trying to squeeze into last year's jeans."