concentrates: High in energy, contains mainly cereal grains and their byproducts, or is prepared from high-protein oil meals or cakes, and byproducts resulting from sugar beets and sugarcane processing. roughages: grass pastures, or plant parts like hay, silage, root crops, straw, and stover. Diets given to different species are all not the same. For example, livestock animals are fed on a diet that consists mainly of roughages, while poultry, swine, and fish are fed with concentrates.