<span>We can conveniently classify feeds into three main types: (1) roughages, (2) concentrates, and (3) mixed feeds. Roughages include pasture forages, hays,silages, and byproduct feeds that contain a high percentage of fiber.</span>
If you are conducting a study on the health of people who have been exposed vs not exposed, the method you should use to obtain data would be an observational study because it involves the pre-existing condition of the subjects.
