Many tens of thousands of tonnes of manufactured feed are consumed by farm animals each year and yet the incidence of infectious diseases contracted from this source is extremely low.
The potential disease hazards include, in alphabetical order, anthrax, botulism, bovine spongiform encephalopathy, foot and mouth disease, listeriosis, Newcastle disease (pigeon paramyxovirus infection), salmonellosis, swine fever and swine vesidular disease. The control of each of these diseases involves a number of different procedures, including the appropriate handling and treatment of the feed, the use of suitable management techniques on the farm, the vaccination of susceptible stock and either the treatment or slaughter of infected animals, or those animals in contact with them.
Several of the diseases (foot and mouth disease, swine fever and swine vesicular disease) have been eradicated from the U.K. while others (anthrax and botulism) occur only infrequently. On the other hand, the presence of salmonellas in feed does constitute a continuing problem since, although organisms do not usually cause disease in animals consuming the feed, they may ultimately cause gastroenteritis in people who either handle or consume meat derived from the animals concerned.