There are many kinds of feed available in the market, each with its own advantages and disadvantages. Forages, such as grass, hay, silage, or alfalfa, are plant-based feeds that provide fiber and energy to your livestock, and are usually the main source of feed for ruminants. Concentrates are high in energy and protein, such as grains, oilseeds, or by-products, and they supplement the forages and enhance your livestock's growth and production. Supplements provide specific nutrients or additives, such as minerals, vitamins, amino acids, enzymes, or probiotics that improve your livestock's health and performance. These are usually fed to all kinds of livestock depending on their needs and deficiencies. Non-ruminants such as pigs and poultry may be fed with concentrates as their main source of feed; however they can also be fed with forages in small amounts. Similarly, ruminants such as cattle, sheep, and goats may be fed with concentrates in moderate amounts.