They usually have a gate that only allows the lambs to get in. Troughs consist of long metal or wood feeders. They can be bought or homemade and are used to feed sheep in a group. Self feeders store feed and let the animal eat as often as it likes. They are recommended for feeder lambs.
Portable feeders are movable and are normally used for one to three sheep.
They can be pans, buckets, or small hanging troughs. They are great for show and sales. Incline feeders are set up with an incline for the front feet of the lamb to stand on so it can eat. These are useful for show and market lambs. This looks like a round circular metal fence with room for the animal's head and sometimes the body.