Dietary Concerns Benefits and Risks or Raw Dog Food (cont.)
Raw Dog Food Diet: What the research shows
Lisa M. Freeman, DVM, PhD, was the lead author on an evaluation of raw dog food diets published in the Journal of the American Veterinary Association in 2001. She cautions pet owners against them, saying that many dog owners are choosing raw diets based on online myths and scare tactics about commercial pet food.
For pet owners who want to avoid commercial food, Freeman advises a cooked homemade diet designed by a nutritionist certified by the American College of Veterinary Nutrition.
Freeman, a nutrition professor at the Cummings School of Veterinary Medicine at Tufts University, says that many of the benefits attributed to a raw food diet for dogs, such as a shinier coat, instead are the result of the high fat composition of the typical raw diet. High-fat commercial foods that would produce the same effect are available, she notes, without the risk of an unbalanced diet. Supplements can also be used as an alternative to increasing fat in the diet.
The evaluation looked at five raw diets, three homemade and two commercially available. All had nutritional deficiencies or excesses that could cause serious health problems when given long term, according to the report.
Joseph Wakshlag, DVM, PhD, has seen those problems appear in some dogs as poor coats, bad skin, or weak bones. Too little fat means a bad coat; but too much fat and not enough protein can cause mild anemia, says Wakshlag, an assistant professor of clinical nutrition at Cornell University College of Veterinary Medicine. (Wakshlag accepts some research funding from Nestle Purina PetCare.) Homemade raw diets also may lack enough calcium and phosphorous, he says, causing bone fractures and dental problems. Depending on the quality of the diet, the calcium or phosphorus may also be difficult to properly digest, even if present in adequate amounts.
Studies of raw pet food also have shown bacterial contamination. The U.S. Food and Drug Administration issued suggestions in 2004 for manufacturing raw pet food more safely, citing concern about the possibility of health risks to owners from handling the meat. A 2006 study of 20 commercially available raw meat diets found that 7.1% contained a type of salmonella. E. coli bacteria was found in 59.6% of raw meat diets. These bacteria can also be shed in the feces, leading to a potential source of human exposure and infection.
The study also sampled four canned and dry dog foods. It found E. coli in all of the commercially processed, cooked foods during one of the four sampling periods, and in one brand of dry food during another sampling period.