Many pet food brands claim blueberries are a source of antioxidants, promoting their health benefits. Blueberries are rich in polyphenols, plant compounds known for their antioxidant and anti-inflammatory properties, which can support human and animal health. For this research, we sampled 40 bags of cat (n = 18) and dog (n = 22) kibble with blueberries listed on the ingredient deck to determine the concentration of quercetin, free phenolics, and antioxidant-protected phenolics. In general, the assessed cat kibble had lower average concentrations of quercetin and antioxidant-protected phenolics when compared to the assessed dog kibble. Concentrations of free phenolics were minimal to nonexistent for all kibble types. The tested extruded kibbles that list blueberries on their ingredient deck likely do not provide enough polyphenols to act as an adequate single source of antioxidants for cats and dogs.

Read the full article in the Journal of Animal Science.