A composition for use in prevention, inhibition and/or treatment of coccidiosis in an animal is disclosed. The composition comprises an effective amount of Bidens pilosa, an active constituent thereof, or an active compound isolated therefrom. In another aspect, a composition for use in enhancing growth in an animal is disclosed. The composition comprising an animal feed and an effective amount of Bidens pilosa, or an isolated active constituent comprising a polyacetylenic compound.