A trip to the vet early in 2005 first made Roy Goodall aware that his Dalmatian, Pongo, was putting on weight. Prompted by the vet’s observation that Pongo could shed a few kilos – he was 35kg (79lb), 6kg overweight – Goodall put his dog on a diet. But, fuelled by an insatiable appetite, Goodall’s inability to say no to Pongo’s demands for pig’s ears, and his unfailing ability to snaffle out discarded chips at the local park, Pongo’s weight continued to rise. The situation became serious, though, when he started to limp.

In March 2006, the vet confirmed that Pongo, then 7, had developed arthritis in his right rear knee. By then a whopping 41kg, the extra weight was putting a strain on his joints. He had to lose weight fast to retain any hope of decent mobility. “Pongo loved playing with his Frisbee but he was unable to run,” Goodall recalls. “After a walk, I could see he was in pain. It was heartbreaking.”

It’s a story that will be familiar to a surprising number of pet owners. Figures suggest that Britain is undergoing a pet obesity epidemic. A survey last July by the pet insurers Sainsbury’s Bank found that 34 per cent of our pet dog population is obese: a figure that would amount to 2.72 million dogs in the UK. And cats are not immune; this month a study by the University of Edinburgh suggests that one British pet cat in 230 is diabetic. Poor diet and lack of exercise is the cause, say the university’s scientists. Meanwhile, in the US this year, the pharmaceutical company Pfizer launched Slentrol, the first obesity drug for dogs. Unsurprising, then, that a host of specialist obesity clinics – or canine fat camps – are cropping up across the UK. So, what’s at the heart of the problem? And how will Britain’s dogs get back into shape?

Dogs are fed high-fat treats

For Pongo the answer came via the People’s Dispensary for Sick Animals (PDSA), a charity that provides veterinary care for pets whose owners can’t pay fees. Every year since 2004 PDSA has invited applications for its Pet Fit Club; the ten picked pets then undergo a 100-day weight-loss regimen.

“I qualified as a vet 30 years ago, and there’s no doubt that I’m seeing pet obesity far more frequently now,” says Elaine Pendlebury, a senior PDSA vet. “As a nation we are less inclined to take long walks, so our dogs get much less exercise. But little treats are usually at the root of the problem. The high-fat, high-sugar foods that people often throw to dogs – bits of ham, digestive biscuits, crisps – just aren’t suitable. You get a cycle of begging, and more food.” Pendlebury cites a daunting list of conditions associated with obesity in dogs, among them diabetes, arthritis, heart problems and joint injuries. “Life for a grossly overweight dog isn’t any fun,” says Pendlebury.

Pongo arrived for his first session at the PDSA centre in Gillingham, Kent, last October. Then he weighed in at 40kg, a hefty 11kg over his target weight. PDSA vets devised a strict diet that would gradually decrease his calorific intake. “I was given a special dry diet pet food and a scoop to measure out 150g twice a day,” says Goodall.

“Pig’s ears were out, and so were all treats. On advice we started a regimen of two 30-minute walks a day, increasing the time as his fitness built. I could see a difference in two weeks; at our first fortnightly weigh-in Pongo had lost 4kg. Within four weeks, he was starting to chase his Frisbee again.”

Owners who allow their dog’s weight to spiral out of control, though, could face more than a friendly trip to the vet. In an unprecedented case in January, the RSPCA brought a successful prosecution against two brothers for allowing their pet labrador, Rusty, to balloon to 74.2kg: so fat, said one vet, that he was, in effect, crippled. David and Derek Benton of Fordham, Cambridgeshire, were convicted of causing unnecessary suffering and received a three-year conditional discharge; they kept Rusty only on condition that he did not regain the 22kg he’d lost while in RSPCA care.

“Pet owners have a duty of care and that includes providing an appropriate diet and suitable exercise,” says Julie Stainton, an RSPCA spokeswoman. “Grossly overweight animals suffer, and this is clearly cruelty. We prosecuted the Bentons only after they repeatedly ignored vet’s advice about Rusty.”

A doggy water treadmill

Now, the RSPCA has launched a travelling road show, Pets Get Slim (www.petsgetslim.co.uk); pets will be weighed in and receive free advice from RSPCA vets. But many owners of portly pooches are already acting under their own steam. The Linhay Veterinary Rehabilitation Centre, in Devon, was established last September. “About 20 per cent of our referrals are for a weight problem, and another 20 per cent have a weight component,” says Kate Rew, the founding veterinary surgeon. “Now, vets are referring dogs to us because they insist that the animal must lose weight before undergoing surgery for another complaint. But increasingly owners are coming, too.”

The centre’s custom-designed answer? A doggy water treadmill. The workout burns a lot of calories but, crucially, is low impact, as overweight dogs often suffer joint problems.

Take Prince, an eight-year-old black labrador who came to the Linhay Centre weighing 75kg; his disabled owner had been unable to exercise him. “Prince could barely walk 20ft; he was huge,” says Rew. “He wouldn’t have seen old age if we hadn’t intervened.”

Over a five-month period Prince’s twice-daily sessions on the treadmill grew from 3 to 30 minutes. By last February he was 53kg; now he is a healthy 41.5kg, a loss of 45 per cent on his starting weight.

“It’s no good labelling pet owners as bad people,” says Rew. “We have to educate them.” It’s a message echoed by Goodall. Last year, Pongo was named the PDSA pet slimmer of the year after losing 9kg – 21 per cent of his starting weight – on the 100-day regimen.

All ten Pet Fit Club participants lost weight in the scheme. Now, thanks to a continued programme of one-hour walks twice a day, as well as strict portion control, Pongo has reached his target weight, a trim 29kg. The pig’s ear habit? He’s allowed one every four weeks.

“I have the old Pongo back; it’s fantastic,” says Goodall. “He’s happy again and bouncing around. Now I look at overweight dogs waddling along and I can’t believe that used to be Pongo.”

The PDSA is searching for pets to take part in the 2007 Pet Fit Club. For more information, visit www.pdsa.org.uk

Getting fit with

Fido Walkies The People’s Dispensary for Sick Animals (PDSA) says an adult dog should have four walks a day, one of at least 30 minutes. A brisk 30-minute walk – with heart rate gently raised – will burn about 125 calories in a typical person.

Cani-cross Short for canine cross-country running. Runners are connected to their harnessed dog by a bungee cord, which links to a belt worn around the waist. It’s a run for both of you, using natural canine pulling instinct. Visit www.canix.co.uk

Agility classes The idea is to get your dog around a series of obstacles in the quickest time possible. Great exercise for your dog and for you. Visit www.agilitynet.com

Football The PDSA says every day should include exercise off the lead. A good game with some friends is to keep a football in action without the dog catching it. Great for honing your footie skills.

When it’s time for din-dins How much in the doggie bowl? How much you feed your dog depends on its size, breed, age and activity levels. Good dog foods come with feeding guides and these are a good place to start. Roughly, a 5kg adult dog will need about one 400g can of wet dog food a day. An adult dog weighing 10kg will need one and two third cans, a 20kg dog will need two and three quarter cans, a 30kg dog will need three and three quarters. Puppies need more food, and old dogs need less. But remember: each dog is different and you should seek advice from your vet.

How often a day? It’s healthier for your dog to be fed more than once a day. For most breeds, a rough guide is two thirds of their food in the morning, one third in the evening. Smaller breeds, such as toy poodles, should be fed more often – perhaps four times a day – because their blood sugar can drop quickly.

In touch with their inner wolf Dogs have a tendency to overeat because they evolved from wolves. Wild animals always eat food when it is there because they can’t be sure when the next kill will come. Dogs are hardwired to behave in the same way, but pet dogs live in very different circumstances and instinct can lead them to eat more than they need.

Give love not chocolate Stop giving treats. What dogs want is your attention; we use food as a replacement. Why not reward your dog with a game instead of food? If you have to treat, the odd bit of boiled chicken is all right.

Time for walkies! A healthy adult dog should have three or four walks a day, one of at least 30 minutes, and including exercise off the lead. ELAINE PENDLEBURY, a senior PDSA vet

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