Nutritive Value of Some Agro-Industrial By-products for Ruminants - A Review

Dumping or burning wastes or agro-industrial by-products present potential air and water pollution problems. High-moisture wastes are also difficult to burn. Many by-products have a substantial potential value as animal feedstuffs. Ruminants, especially, have the unique capacity to utilize fibre, because of their rumen microbes. This means that cereals can be largely replaced by these by-products. Consequently the competition between human and animal nutrition can be decreased. Nevertheless, there is an increased cereal supply owing to genetic and management improvement. The utilization of agro-industrial by-products may be economically worthwhile, since conventional feedstuffs are often expensive. However, livestock have historically utilized large amounts of well-known and widely-available traditional by-products such as oil meals, bran, middlings, brewers' grains, distillers' grains, beet pulp and molasses. But less conventional by-products have become available, such as vegetableand fruit-processing residues, whey and culinary wastes. This review evaluates some of By-products in regard to their characteristics, nutritive value and their digestibility.