Weeth Nutrition Services, City of Angels Veterinary Specialty Center, Los Angeles, CA, USA
Feeding a complete and balanced diet is known to promote wellness in dogs and cats, but a number of highly publicized pet food recalls, as well as a growing appreciation for the role of diet in health and disease, has raised questions about the use of commercial pet foods to meet this end. Additionally, concerns over specific ingredients, such as corn or wheat, have been promoted through advice columns and pet food marketing companies and has caused some owners to become leery of manufacturers that incorporate these ingredients into their foods. Many owners, and some veterinarians, also advocate feeding dogs and cats home prepared foods exclusively (raw or cooked, or both) and either cite perceived health benefits or a general mistrust of the pet food industry. At its most basic concept, food is a means of getting essential nutrients into the body. How these nutrients are delivered or which specific ingredients are being used (barring ingredient sensitivity) is much less important than ensuring that the optimal amount is provided on a regular basis. Whatever the reason for a particular diet strategy, it is important for veterinarians to understand the motivations, risks, and benefits of that diet type to ensure that the nutritional needs of the individual animal are being met.
Homemade vs. Raw
Home-prepared diets have grown in popularity over the last few years. For some pet owners it is in response to concerns about the production of commercial diets, for others feeding home-prepared foods reinforces the human-animal bond, and for still others a home prepared diet is required to manage a medical condition. Proponents of home-prepared foods claim that these diets are a safe and natural way to feed animals. It is true that fresh meat whether it is fed raw or cooked is palatable to most dogs and cats, can be highly digestible, and depending on the cut of meat selected is higher in fat than most dry kibbles. The result is an animal that readily eats its food, has low stool volume, and a shiny coat. These positive aspects are often held up as proof of nutritional superiority to commercial foods, while ignoring the potential negative consequences.
The negative aspects of raw diets can be disastrous for the animal and the people in the household. Any raw meat ingredients can be a potential source of parasitic and bacterial exposure, which can include Neospora, Toxoplasma, Salmonella, E. coli, Campylobacter, and Cryptosporidium. While healthy adult dogs and cats may resist disease induced by these pathogens, young or immune-compromised animals are at a risk of illness and death with exposure. Otherwise healthy adult animals fed raw meat diets also serve as a source of contamination to people and any other animals in the household. Raw and cooked bones specifically carry a risk of gastrointestinal obstruction/perforation and oral trauma and are a poor source of essential minerals (such as calcium, phosphorus, and magnesium) due to the poor digestibility of larger bones within the canine and feline digestive tract. Ultimately, the animal’s acceptance of a home-prepared diet does not change significantly when the meat is cooked or when more bioavailable sources of nutrients are used.
Published reviews of the nutritional adequacy of home prepared (cooked and raw) diet recipes in recent years found that less than half of the recipes used by the pet owners provided a complete and balanced source of nutrients. Unless someone with veterinary nutrition training developed the diet, there are a few consistent deficiencies found in most home prepared recipes irrespective of the ingredients used. Most home prepared diets for dogs and cats are lacking a sufficient source of calcium; a source of trace minerals (such as iodine, selenium, copper, and zinc); a source of linoleic acid; and a source of essential fat-soluble and water-soluble vitamins. While the perceived benefits of home prepared diets are reinforced daily to the owner, nutrient deficiencies in adult animals are insidious and can lead to long-term complications, which can vary from poor skin and coat health to chronic diarrhea, osteopenia, anemia, altered drug metabolism, and hepatic lipidosis depending on the specific nutrients lacking in the diet.
Individual animals may vary in their response to specific commercially-available diets and there is no one dietthat-fits-all. If an owner elects to feed a home prepared diet they should be counseled on the risks of this feeding strategy and cautioned that nutritionally-related disease can mimic other forms of chronic illness. Any animal eating a home-prepared diet should have at least an annual physical exam and health screening, including serum biochemistry (with T4), hematology and urinalysis profiles. While blood work and urinalysis results will give you a general overview of the animal’s health status, it will not pick-out specific deficiencies or excesses.
A complete diet history (all foods and supplements) should be collected from the owner at each visit. Any home prepared diet recipes should be obtained from a reputable, trained source. Additional resources, including a list of board-certified veterinary nutritionists, can be found through the American College of Veterinary Nutrition (www.acvn.org).
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