Raw Feeding - Bacteria, Viruses and Parasites

Bacteria, Viruses and Parasites

While the intense heat used in manufacturing pet food or cooking meat destroys any potential bacteria, raw meats may contain bacteria that are unsafe for both dogs and cats. The U.S. government reported that in 2006, 16.3% of all chickens were contaminated with Salmonella. A study on 25 commercial raw diets for dogs and cats detected salmonella in 20% and Escherichia coli in 64% of the diets. However, the E. coli strain that can cause severe illness O157:H7 was not tested for. An example of the severity of E. coli H157:O7 infections can be seen in affected greyhound racing dogs fed raw meat as part of their diet. Known in greyhounds as "Alabama rot", the disease causes severe vasculitis, cutaneous necrosis, renal failure and death. It should be noted that racing greyhounds are typically fed raw meat classified as "not for human consumption", which may contain higher than normal levels of bacteria.

Raw feeders claim that the stomach enzymes and short intestinal tracts of dogs and cats allow them to handle harmful bacteria. There has been a reported case where two cats fed a raw diet developed salmonellosis and died as a result. A veterinarian from the National Animal Poison Control Center suggests that the diarrhea in animals that raw feeders attribute to detoxing could be caused by pathogens such as Salmonella, E. coli, Clostridium and Campylobacter. Bacteria proliferation in any meat can be reduced by following proper food safety practices such as defrosting meat in the refrigerator; harmful bacteria can be largely eliminated from meat by cooking.

Raw meats may also contain harmful parasites. As with bacteria, these parasites are destroyed during the heat processing of cooking meat or manufacturing pet foods. Some raw diet recipes call for freezing meat before serving it, which greatly reduces (but does not necessarily eliminate) extant parasites. According to a former European Union directive, freezing fish at -20°C (-4°F) for 24 hours kills parasites. The U.S. Food and Drug Administration (FDA) recommends freezing at -35°C (-31°F) for 15 hours, or at -20°C (-4°F) for 7 days. The most common parasites in fish are roundworms from the family Anisakidae and fish tapeworm. While freezing pork at -15°C (5°F) for 20 days will kill any Trichinella spiralis worm, trichinosis is rare in countries with well established meat inspection programs, with cases of trichinosis in humans in the United States mostly coming from consumption of raw or undercooked wild game. Trichinella species in wildlife are resistant to freezing. In dogs and cats symptoms of trichinellosis would include mild gastrointestinal upset (vomiting and diarrhea) and in rare cases, muscle pain and muscle stiffness.

A survey of accredited zoos worldwide showed a slightly increased risk of parasites and diseases in animals that are carcass fed as compared to commercial food fed. However, the researchers suggested that that may be caused by increased opportunistic preying and infected live preys may be the source of contamination.