Adult weevils have elongated heads that form a distinct “snout.” | Photo: iStock

A: This time of year, owners occasionally find what appear to be beetles in bags of horse feed. These beetles could be bran bugs or weevils, especially if the feed contains whole grains. You can tell weevils apart from other bugs by the shape of their head—adult weevils have elongated heads that form a “snout.” Bran bugs look like weevils, but without the snout.

Weevils live inside and damage whole grain kernels; however, neither they nor other bugs commonly found in grain pose a risk to your horse. That said, such bugs could lower the feed’s nutritional content if they, themselves, are feeding on it. Bran bugs live on broken grain and grain dust.

You might also see meal moths, which tend not to discriminate the same way weevils and beetles do and will attack all forms of grain. The moths lay eggs on the grain’s surface. The eggs then hatch into caterpillars that look like little worms. These larvae create a web over the grain that impacts air movement and results in grain clumps