FODDER CROPS are crops that are cultivated primarily for animal feed. By extension, natural grasslands and pastures are included whether they are cultivated or not. Fodder crops may be classified as either temporary or permanent crops. The former are cultivated and harvested like any other crop. Permanent fodder crops relate to land used permanently (for five years or more) for herbaceous forage crops, either cultivated or growing wild (i.e. wild prairie or grazing land), and may include some parts of forest land if it is used for grazing. Temporary crops that are grown intensively with multiple cuttings per year include three major groups of fodder: grasses, including cereals that are harvested green; legumes, including pulses that are harvested green; and root crops that are cultivated for fodder. All three types are fed to animals, either as green feed, as hay, i.e. crops harvested dry or dried after harvesting, or as silage products. Silage, or ensilage, refers to green fodder preserved without drying by fermentation that retards spoiling. Some fodder crops are components of compound feeds. Grasses contain crude fibres, crude protein and some minerals. Legumes are particularly rich in proteins and minerals. Root crops are high in starch and sugar and low in fibre, making them easy to digest. The fibre content of most fodder crops consists of cellulose, a complex carbohydrate polysaccharide that is indigestible for humans, but which is a good source of energy for animals, and particularly ruminants. For reporting purposes, the aggregation of various fodder crops into "feed units" is expressed in different ways in different countries. For example, aggregations are reported in terms of metabolizable energy, digestible nutrients, starch equivalent, protein equivalent, or grain equivalent. The FAO list includes 17 primary crops. The code and name of each crop appears in the list that follows, along with its botanical name, or names, and a brief remark where necessary.
PRODUCTS USED FOR ANIMAL FEED include: processed products from fodder crops; waste and residue; manufactured compound feeds, consisting of various mixed feeds of vegetal and animal origin to which minerals and vitamins have been added; and chemical preparations, such as vitamins and minerals and various additives. The FAO list includes 21 products, in addition to products that are already listed under other headings.