Feeding pigs recycled human food must be done under strictly-controlled conditions, otherwise a producer risks deadly pig diseases, such as foot-and-mouth, classical swine fever and African swine fever, according to the National Pig Association.
These highly infectious diseases, which can be introduced in infected meat - even meat that has been processed and cooked - are economically damaging to a producer and the only effective way to control them is by widespread slaughter of livestock.
NPA's warning comes as "Pig Idea" environmental campaigners call for more left-over foods to be fed to pigs as swill. While recognizing that feeding pigs properly-treated and rigorously-tested foods such as unsold bread and vegetables can deliver significant environmental benefits, NPA warns that there is always a risk of regulatory breakdown, as happened in the 2001 national foot-and-mouth outbreak, when infected swill was fed to pigs on a Northumberland unit in the UK.
"We don't want this campaign to give the public the mistaken impression that it is alright to feed waste food to pigs," says Dr. Zoe Davies, general manager of the National Pig Association.
Feeding waste food from catering establishments including home kitchens and restaurants - even if it is only vegetables - has been banned in the UK since the 2001 national foot-and-mouth outbreak, which devastated countryside tourism and livestock farming and more than 6 million farm animals to be compulsorily slaughtered.
The law also covers food waste from other premises, including food factories and distribution warehouses that contains or has been in contact with animal by-products such as raw eggs, meat and fish products. None of these items may be fed to pigs, including pigs kept as pets.
"We appreciate that the Pig Idea campaigners have the best of intentions and have been at pains to explain all the legal issues but we remain concerned that promoting the image of pigs eating waste food is unhelpful," says Davies. "The pig industry already uses more than 1 ton per year of by-product from food manufacturing, but only as part of a tightly-regulated and audited process."