Comparison of mycotoxin concentrations in grain versus grain-free dry and wet commercial dog foods

Abstract Mycotoxins are secondary fungal metabolites that cause both acute and chronic disease in humans and animals. Grains are a common substrate for molds and the production of mycotoxins. This study compared mycotoxin concentrations between grain and grain-free commercial dog foods. In total, 60 samples of dry and wet dog foods produced by five major manufacturers within the US were purchased from pet food retailers in southern California. A standard mycotoxin panel was performed by a reference laboratory in Seattle using industry standard methodology for pet foods. Results of the study demonstrated measurable mycotoxin concentrations in dry dog foods containing grains but not in grain-free dry dog foods, or in wet foods either containing grains or grain-free. This study suggests that the risk of mycotoxin exposure is higher in dry dog foods containing grains. To mitigate this risk, dog food manufacturers could incorporate grains that are categorized as US No. 1 by the USDA and therefore less susceptible to mycotoxin formation