Detailed, long-term feeding trials may help pet food companies avoid nutrition-related crises, such as the U.S. Food and Drug Administration’s announcement about canine dilated cardiomyopathy’s correlation with certain grain-free dog foods. Then again, maybe not, since feeding trials might overlook breed-specific dietary needs and other factors, according to veterinary nutrition scientists at the University of California – Davis.
Those scientists published research on nutrition’s relationship with DCM: “Taurine deficiency and dilated cardiomyopathy in golden retrievers fed commercial diets,” in the journal PLOS ONE.
The researchers, Jennifer A. Larsen, DVM, PhD, professor of clinical nutrition in the veterinary medicine program of the University of California – Davis, and her co-authors, answered Petfood Industry’s questions about the interactions among feeding trials, nutrition and disease in an email.
1. In the PLOS ONE article you wrote, “None of these diets were feeding-trial tested using Association of American Feed Control Officials (AAFCO) procedures.” Could you comment more on the use of feeding trials in the current pet food industry? If there is an issue, what would you recommend to address it?
Larsen: The use of feeding trials for nutritional adequacy is not as common as perhaps it should be. The AAFCO protocols as outlined in the annual OP outline minimum assessment parameters, but manufacturers can and should consider additional or more stringent procedures or testing. For example, the addition of plasma amino acid assessments might be useful, or protocols can be conducted for a longer period of time.
2. Could controlled feeding trials have altered, or avoided, the current situation with DCM and certain dog foods?
Larsen: This remains unknown since the exact mechanism has not been characterized. In addition, if there are breed or individual factors that predispose dogs to nutritionally mediated DCM, this might not be documented in feeding trials using subjects that do not share those characteristics. On the other hand, until we investigate this issue further, it remains possible that feeding trials that include assessments for amino acid adequacy would provide useful information to pet food formulators and other scientists.
3. What could formulators of breed-specific pet foods learn from your research?
Larsen: It is possible that breed differences in nutrient metabolism could inform pet food formulation and testing. Individualized nutrient requirements for dogs or dog breeds have not been well defined at this point in terms of scientific support. However, at the very least, it may be warranted to test diets in different sized dogs, given the known differences in diet digestibility and fecal water content, etc. among breed sizes.
4. Genotyping of dogs has grown in popularity. Are there any genes identified as influencing taurine deficiency risk?
Larsen: There is some support in the literature to consider that there may be some breed-specific risks for this condition. In our most recent data set, this condition does not appear to be familial. We continue to look at breed specific genetic considerations that may impact this condition. Some other work has been previously done in this area. See:
