nutrient characteristics (U.S. Department of Agriculture, Agricultural Research Service, 1991). It is important that these variations be identified and reported accurately in a North American feed information system to reflect the changes in nutrient content for use in animal production, as well as to reflect the economic value of these products in agricultural trade.

Complementing advances in genetic engineering and sustainable agriculture systems, and a key component in integrating these diverse agricultural sciences, is the use of information technologies that have a positive influence on agriculture's environmental impact. A North American feed information system could be an essential link uniting different areas of environmentally sound science and enhancing achievements in each area, whether in animal nutrition, bioengineering, sustainable agriculture, or agricultural education.

There is general agreement that some type of regulation needs to be in place to monitor nutrient concentrations and contaminants that may affect animal and public health. A major concern, however, is the point of reference on which regulatory decisions are based. The specific processes and analytical methodologies used to establish the tolerance concentration of a nutrient or contaminant may be on the basis of a single and often nonrepresentative number. A comprehensive feed data base must include a variety of conditions under which feed is processed or manufactured to yield a concentration range rather than a single concentration for a specific component. Making decisions based on more extensive data would add credibility and accuracy to the regulatory process.

In the United States, the safety of most food and feed ingredients is regulated by the Food and Drug Administration (FDA) under various provisions of the Food, Drug, and Cosmetic Act (Public Law 98-80). U.S. government policy extends existing laws to the regulation of food products, especially those modified by biotechnology. When regulatory agencies review new or modified feed ingredients to be used in livestock feed, they must have accurate data that they can use to evaluate the safety of those particular ingredients.

Present laws recognize that the natural food supply contains many substances that, when isolated and consumed in large amounts, may be toxic but that are neither toxic nor harmful when consumed as inherent constituents of feeds. However, mycotoxins, which are toxic metabolites of fungal contaminants of feed grains, can be harmful to animal and human health. Aflatoxin has traditionally been the major mycotoxin of concern to animal producers. More recently, fumonisin, vomitoxin, and others have increasingly become more prevalent and pose a risk to animal health (Marquardt and Frolich, 1992; Rotter et al., 1994;