The latest edition of the Journal of the American Veterinary Association features a study of homemade recipes for maintenance diets for dogs. The results are dismal. It demonstrates how difficult this process really is and how important extensive research is needed to create a balanced homemade diet.
The Study Recipes
The researchers analyzed 200 homemade recipes. 67% of the recipes were from two veterinary textbooks and nine pet care books. Four of these sources were authored by board certified veterinary nutritionists. The other 33% of the recipes were obtained from 23 different websites. 64.5% of the recipes were written by veterinarians and 35.5% of the recipes were authored by non-veterinarians.
Of the 200 recipes, only nine recipes met or exceeded the National Research Council’s (NRC) Recommended Allowances or Minimum Requirements for all essential daily nutrients. Nine recipes exceeded the nutrient minimums established by the Association of American Feed Control Officials (AAFCO). All but one of those recipes meeting the NRC or AAFCO standards was authored by a non-veterinarian.
95% of recipes authored by both veterinarians and non-veterinarians were deficient for at least one nutrient and 85% had multiple deficiencies. The most common deficiencies were zinc, choline (a vitamin-like nutrient), vitamin D, vitamin E, copper, calcium and EPA/DHA (omega-3 fatty acids). In some of the deficient diets, deficiencies of vitamin D, vitamin E and choline were less than 50% of the NRC Recommended Allowances.
Nine recipes exceeded the NRC Safe Upper Limit for vitamin D, and six recipes exceed the Safe Upper Limit for EPA/DHA. 6.5% of the recipes included garlic or onions, which are considered toxic to dogs because of their potential to cause the destruction of red blood cells and lead to anemia.
92% of the recipes were vague and required one or more assumptions on the part of the owner concerning actual ingredients, preparation method or supplements. 29% of the recipes did not even include necessary supplements. 85.5% of the recipes did not include feeding instructions.
The findings in this study verify my observations when I started my research on homemade diets. The lack of attention to detail by veterinarians, even those who are board certified in nutrition, and non-veterinarians may have serious long term problems for those wishing to feed quality homemade diets. We are already beginning to see an increase in puppies and dogs with osteoporosis presenting in veterinary hospitals.
The upside of the study is that it verified that recipes analyzed by available databases of human foods (providing that specific preparation was followed) were consistent with the chemical analysis of randomly chosen recipes. This means that if an author of a homemade recipe can provide a USDA database comparison of their recipe compared to NRC and AAFCO requirements for all essential nutrients (42 for dogs and 44 for cats) then the recipe is probably adequate.
The researchers of the study suggest that recipes include a safety margin of quantity of nutrients to allow for individual difference in digestibility and absorption of nutrients. Such recipes should exceed both NRC and AAFCO for all nutrients without exceeding the Safe Upper Limits. Table 1 is an example of the type of information that an author, or commercial food manufacturer for that matter, should be able to provide.
The amino acid taurine and the essential fat arachadonic acid should be included for cats. They should also specify the supplement brands that will provide the necessary levels of nutrients. If they are unable to provide all of this information, keep searching.
Dr. Ken Tudor