SPOILAGE AND PATHOGENIC MICROORGANISMS IN ANIMAL FEED

Fungi are the principal cause of spoilage of animal feed, particularly cereals and legumes. In addition, some fungal species may elaborate toxins which cause serious disease in animals consuming the feed. Bacterial spoilage may also occur although the problem is relatively uncommon because the water activity of dry feed is too low to permit bacterial multiplication. Animal feed may be the source of several pathogens. The virus diseases such as classical swine fever, foot and mouth disease, Newcastle disease and swine vesicular disease, together with bovine spongiform encephalopathy, are notifiable in the UK and legislation exists to minimise the risk of the causal organisms being spread by animal feed. Anthrax, listeriosis and salmonellosis are examples of bacterial diseases that may be contracted following the consumption of contaminated feed, and botulism is associated with the ingestion of preformed toxin.