A dog owner loves the site of his or her pooch resting comfortably on the floor or eager to play.

But sometimes, you take a look and realize ol' Sparky looks a little softer than he used to. Maybe it's a few too many table scraps or not enough active time. But how can you tell if your pet has packed on too many pounds and could use a few more trips to the dog park?

PetEducation.com says that a veterinarian checks for obesity -- or being too thin -- by checking out the whole body, especially parts where bones should be easily felt. That includes the ribs, the base of the tail, the spine, shoulders and hips.

In those areas, it should be easy to feel the bones along with a covering of fat that feels smooth. If the bones are hard to appreciate, the dog is likely overweight or obese.

Also, dogs should have a waist behind the ribs when seen from above. When viewed from the side, there should be an abdominal tuck where the body goes up behind the ribs, though the difference can vary based on breed. Diagrams of these features can be found at ZoneDogs.com.

A dog that seems to have trouble getting around or loses interest in activities may also be a sign of carrying too much weight, according to VetMedicine.com.

Besides not looking right and leading to a less interested pal, being overweight can cause serious health problems for a dog. BillFoundating.org says the complications include diabetes, joint and bone damage, heart disease, breathing problems, digestive disorders and an increased risk of cancer.

If you do have an overweight pet, most experts suggest adding more gentle exercise, cutting down on meal sizes and cutting back on treats and scraps to help your dog get to a healthier weight.