We’re probably used to seeing rosemary in sprig form, on our roast chicken or turkeys. In dog food, rosemary actually plays a role as a natural preserving agent. The herb is sometimes used in extract form rather than oil form, and often replaces synthetic agents such as BHA. It contains free radical-fighting antioxidants, and AAFCO-approved dog food will usually have only a small amount of it. Some dogs have been known to react badly to rosemary, so always consult your vet if you have concerns about your pet’s health.