A feed supplement having a botanical component and a nutritional component. The botanical component comprises cinnamaldehyde, carnosic acid, rosmarinic acid, carvacrol, thymol, capsaicin and curcumin. The nutritional component includes zinc, copper, chromium, and vitamin B. Also provided is a method for improving the nutritional status, such as increasing lean muscle mass, of pigs or other livestock. The method includes feeding to the livestock a composition having a botanical component, including cinnamaldehyde, carnosic acid, rosmarinic acid, carvacrol, thymol, capsaicin and curcumin； and a nutritional component including zinc, copper, chromium, and vitamin B.
