Last modified: Thursday, March 29, 2007 1:30 AM EDT ELiz Bethoney, a technician for the Norton Animal Hospital, feeds Miss Angus, right, a border collie -- English sheep dog mix, owned by Jane Donlon of Mansfield. (Staff photo by MIKE GEORGE) Food for thought for pets BY RICK FOSTER SUN CHRONICLE STAFF A poisoning scare that forced the recall of more than 90 brands of dog and cat foods recently has pet owners thinking not only about safety but proper nutrition for their pet. And what they don't know could hurt their canine and feline friends. "A lot of people come in and say they've done their own research, but it's a complicated subject," said Bob Bamberg, owner of Attleboro's Old Barn, a major pet food retailer. "There's a lot to know." Veterinarians and pet nutritionists say members of the public are hitting Web sites and hot lines with questions about pet foods after pet foods believed to be contaminated by rat poison caused the deaths of as many as 104 animals. The maker of the foods has acknowledged only 16 deaths. A nationwide recall affected a large number of brands because wheat, an ingredient often found in dog and cat foods and the contaminated ingredient linked to pet deaths, is present in many feeds. But finding the best nutrition for man's best friend isn't as easy as many pet owners think. Many brands claim to be superior "all purpose" foods or the best for puppies or older dogs. But few include even basic nutrition information in their advertising. "The labeling of many foods is misleading," said Dr. Tom Silberhorn, a veterinarian with the Norton Animal Hospital. "Some will say the product is a good 'all purpose food,' for instance, when that's really not possible." Dogs and cats have nutritional requirements that may vary throughout their lifetimes, Silberhorn said. Similarly, claims by dog food makers that their products are "all natural" do not necessarily mean they offer better nutrition. "You really have to look at the ingredients and the calories listed on the label to decide what's best," he said. Leslie Blanchette, an instructor and nutrition expert at the Bristol County Agricultural School, said animals may require different foods and ration sizes depending on their lifestyle - a hunting dog may require different nutrition than a companion animal, for instance. "It's always advisable to check with your veterinarian to decide what's good for your individual pet," she said. Price isn't necessarily a guarantee of quality, either, says Blanchette, since many high-priced foods can include large amounts of filler. It isn't easy being a discerning pet owner when it comes to buying food for your dog or cat, says Attleboro's Old Barn's Bamberg. But some basic concepts are helpful. Dog and cat food makers spend lots of money on advertising and packaging to make their products look like the best nutrition for the money. But producers can't hide from labeling requirements which list ingredients in the order of greatest quantity. The first ingredient in any list is the single largest component in the makeup of the feed. "If you see a dog or cat food and the first ingredient is corn, that's not a high quality food," Bamberg said. Not only do many dog and cat foods have large quantities of processed corn, they also contain soybeans, wheat and other fillers that often are not tolerated well by the animals. Wheat, for instance, can contribute to dry skin, while grains in general are difficult for dogs and cats to digest. Although some non-meat items in pet foods like rice are better, Bamberg says, feeds that contain a preponderance of fillers aren't the best nutrition. Higher quality dog and cat foods, called "super premium" or "organic" foods may include extra nutritional value in the form of minerals that are chemically bound to proteins to aid absorption or supplemental amounts of bacteria normally found in a dog's intestines to facilitate digestion. Although "super-premium" and other elite feeds generally cost more than the supermarket brand, consumers may actually save money because a dog or cat being fed superior quality food usually requires smaller amounts of it than a filler-laden variety. One popular brand recommends an eight-cup serving of its kibble each day to feed a 100-pound dog. By comparison, Bamberg displayed a higher-priced super premium brand that recommends a 4-cup serving for the same animal.