Dear Christopher Cat: Should we feed our cats dry food or canned food?

Christopher responds: You may want to consider both.

Many families feed only dry food, primarily because it's convenient. An added benefit is that dry food, particularly if it's recognized as a dental diet by the Veterinary Oral Health Council (www.vohc.org), minimizes dental plaque and tartar.

However, our mom supplements our dry kibble with canned food. She wants us to like canned food, in case we need to eat it in the future. For example, cats that develop bladder or kidney disease require extra water, and canned food is a good source because it is about 80 percent water.

New research reveals that a canned diet also decreases the risk of diabetes in cats.

In a study of 2,066 cats, 396 of whom had diabetes, researchers learned that cats fed diets containing at least 75 percent dry food were at increased risk of diabetes, even when their weight was reportedly normal.

Veterinarians have long known that obesity predisposes cats to diabetes. This new study also showed that "greedy eaters," cats who finish their meals immediately, have a higher risk of diabetes than cats that nibble throughout the day.

Other risk factors for diabetes include being male, having received steroid injections and living without dogs or other pet species in the home. Indoor living also increases the risk of diabetes, unless the cat leads an active lifestyle.

While a combination of dry and canned foods may be best for most cats, only your veterinarian can recommend a diet to meet your own cats' needs. Ask at your next visit.

°°°

Dear Daisy Dog: Floyd, our 8-year-old, unneutered Boston terrier, suddenly developed a large swelling on one side of his anus, and he strains to move his bowels. Is this an impacted anal sac?

Daisy responds: It may be, or it might be a mass in or near his anal sac, but it's more likely a perineal hernia. Regardless, Floyd should see his veterinarian immediately.

A perineal hernia is protrusion of abdominal organs through a tear in the pelvic muscles. These hernias may develop on one or both sides of the anus.

The condition occurs most often in unneutered male dogs, particularly those that are middle-aged and older. Breeds most commonly affected are the Boston terrier, boxer, collie, old English sheepdog and Pekingese.

If Floyd has a perineal hernia, he will need surgery to repair it. He should be neutered at the same time to reduce the risk of recurrence. Fortunately, the prognosis following surgery is excellent.

If the swelling is just an impacted anal sac, your veterinarian can relieve the impaction before the anal sac ruptures.

Make an appointment now, so Floyd will feel better soon.

Ask the Vet's Pets appears Friday. The animal authors of the column live with Lee Pickett, V.M.D., who practices companion animal medicine. Contact them at www.askthevetspets.com.