It is instructive and relevant to provide a brief review of the regulatory prospects for the control of undesirable substances. Currently, regulations are most comprehensive in Europe and North America, while in developing countries statutory directives may not even exist. Thus, 50 countries, mostly in Africa, have no regulations for mycotoxin control (D'Mello and Macdonald, 1998). This situation may be changed by the new rules imposed on feeds imported into the EU which came into force in August 1999. Non-EU feed manufacturers are now required to have representatives based in the EU who can confirm declarations concerning certain quality and safety standards for imported animal feeds.
For heavy metals and aflatoxins, distinctions in prescribed limits are generally made for straight, complete and complementary feedstuffs. Additional distinctions may apply according to the destination of feeds for a particular class of animal. For controlled pesticides, separate regulations exist for feedstuffs and for fats, with virtually no distinction for the class of animal. Of the wide variety of plant toxins, only gossypol, cyanogens and certain glucosinolates are subject to regulatory control in the EU. Special regulations apply to contamination of feeds with specific bacteria. For example, under United Kingdom regulations, positive identification of Salmonella in feeds must be reported to a "veterinary officer of the Minister" (HMSO, 1989).
Specific regulations apply to the control of BSE in cattle. For example, in the United Kingdom, it has been illegal to feed ruminants with any form of mammalian protein since November 1994. The feeding of mammalian meat- and bone-meal (mMBM) to farmed livestock has been prohibited since April 1996. However, pigs and poultry may still be fed diets containing mammalian protein in forms other than mMBM, e.g. processed catering waste. Surveillance results of animal feeds indicate widespread compliance with these regulations, with 99.7 percent of feeds found to be negative for mammalian protein.
