Andy Starnes, Post-Gazette photos
	Molly Youngling's 11-year-old indoor cat Zippy weighs in at a hefty 40-or-so- pounds.
	IS FIDO TOO FAT? HERE'S HOW TO FIND OUT: RIB CHECK: Place both thumbs on your pet's backbone and run your fingers along his rib cage. If you can't easily feel his ribs with slight pressure, he's probably overweight. PROFILE CHECK: Take a look at your pet from the side. If he's at the proper weight, you should see a clearly defined abdomen. OVERHEAD CHECK: Stand directly over your pet while he's standing up. You should see a clearly defined hour-glass shape; if not, he's too heavy. More weight tips for your pets
	Zippy wakes up from a nap in the bathtub, one of his favorite spots for relaxing.

In this era of pet resorts, doggie yoga, feng shui pet gardens and Retin-A acne treatments for cats, it was just a matter of time.

A weight-loss contest for your pet.

Your dog or cat can win money, a year's supply of pricey pet food and free airline tickets to stay at an "upscale pet-friendly hotel" by entering Hill's 2006 National PetFit Challenge. The contest started in mid-April and ends Sept. 1.

As over-the-top as this marketing ploy may sound, controlling proper weight in your pet is a serious matter.

One of every four dogs and cats in the Western world is obese, according to the landmark 2003 report from the National Academy of Sciences. Researchers compiled the 450-page report after reviewing 25 years of scientific papers on cat and dog nutrition.

"Like humans, dogs and cats that are obese run a higher risk of developing diabetes, heart disease or other problems," according to the report.

The report sets new dietary guidelines for dogs and cats, including specific nutrient requirements for protein, fat, vitamins, minerals, carbohydrates, fiber and additives.

"The overweight dog is overloved,' said Dr. Lawrence Gerson, a veterinarian in Point Breeze who has started a regular weigh-in program to monitor some of his pudgy patients. Many of the owners don't recognize that their pets are larger than they should be.

"You have to be gentle with owners,'' he said. "You don't want to offend them, but I will tell them" about the health perils they face.

One study done by a pet food company, he notes, showed that dogs on reduced diets lived two years longer than "free-fed" dogs that ate as much food as they wanted.

The solution is to reduce the amount of food given to pets (no more table scraps!) and to increase their exercise.

But that can be far simpler to control for a dog than a cat, as one Shadyside cat owner can attest.

Molly Youngling's 11-year-old indoor cat Zippy ("The Zipster") looks more like a Buddha than a cat, at an estimated 35 to 40 pounds.

He's also three times larger than the other four, slender cats that she owns. All of her cats are spayed or neutered, which reduces by 5 percent the total number of calories they need each day.

Like most cat owners, she keeps dry food out all the time, as cats tend to eat small meals all day. In the morning, she spreads the contents of one can of meat among the food dishes.

"If I changed that routine, I'd have a bunch of crying cats all the time," she said.

She's never been admonished by her vet for Zippy's girth. Other than the fact he moves slower these days and snores, he seems fine.

Not surprisingly, the $35.9 billion pet supplies and services industry is pumping out all sorts of low-fat/low-calorie chow and weight-loss strategies for its four-legged consumers.

Although a Pet Weight-Watchers program has yet to hit the market, Dr. Gerson, the Point Breeze vet, is trying something similar in his practice.

He recommends that owners weigh or measure the daily food portions. If the dog or cat is not losing weight, gradually decrease the amount of food given each day, including treats.

A dizzying array of pet health, diet and fitness books are now on the market. Released this month, "Fitness Unleashed! A Dog and Owners' Guide to Losing Weight and Gaining Health Together," estimates that close to 30 million dogs in the United States are obese.

Written by veterinarian Marty Becker of Bonners Ferry, Idaho, and medical doctor Robert Kushner, a professor of medicine at Northwestern University near Chicago, the book aims to help both dogs and their owners.

"Many of us have shared our generous [food] portions and inactive routines with our pets," writes Dr. Becker, who is a regular contributor to ABC's "Good Morning America."

"Centuries of species' self-preservation have left most dogs with a strong desire to consume any edible bite they can find. They've historically survived as scavengers. ... Many will eat as much and as often as you'll let them."

Their book was inspired by the Hill's People and Pets Exercising Together (P-PET) study, which started three years ago. Pets and their owners ate low-calorie diets and exercised together for one year. They lost weight and kept it off.

The study concluded that the program had a higher rate of success because the pets were included. Moreover, the pets that were exercised regularly were happier and had fewer behavior problems.

A spin-off of this is the National PetFit Challenge, which involves Dr. Becker as a contest judge. Also participating -- but not competing -- with her rescue Chihuahua named Baxter is Jillian Michaels, one of the exceedingly fit personal trainers on the NBC series "The Biggest Loser."

Although she's kept herself in top shape, the same can't be said for Baxter, who, at 11 pounds, is 3 pounds -- or 30 percent -- heavier than his ideal weight of 8 pounds. As a result, he looks more like a pug than a Chihuahua.

Exercise plans for dogs and people work well, Dr. Becker said in an interview, "because people stick to it because their dogs love it so much.

"There's nothing like a dog getting you off the floor and out the door."