Salmonella levels down in abattoir pig carcasses

Pig producers must improve food safety and animal health while reducing risks to public health, according to Derek Armstrong, head of research and development at BPEX.

Speaking at a national meeting on key diseases in pigs and their transmission to humans last week, Mr Armstrong said: “Our standards of biosecurity have never been more important than today to eliminate or control significant enzootic pig diseases.”

The higher welfare standards from the 20:20 pig health and welfare strategy will come with environmental challenges for outdoor herds and risk of increased contact with faeces for those indoors, added Mr Armstrong. However, results from a study of disease in pigs at slaughter in 2013 showed some positive results.

Key findings

Salmonella levels in the carcass decreased from 15% in 2006-07 to 9.6% in 2013. The AHVLA said this was due to improved abattoir procedures. However, there was also an increase in salmonella found in the large intestine, from 22% in 2006-07 to 30.5% in 2013, indicating biosecurity on farm could be tightened.

See also Farmers can register for the BPEX farm risk tool to identify the highest salmonella risk areas and most effective control methods on their farm.

For the first time, a UK-wide study of Yersinia – a bacterial disease passed from pigs to humans causing diarrhoea and arthritis – showed about 2% of carcasses tested positive, so risk to consumers is low. This is an important finding, considering pigs are considered to be the primary reservoir for human infection, said the AHVLA.

Toxoplasma was also included on the UK-wide survey for the first time and findings showed 7.4% of pigs had antibodies to the infection. This is a low risk to consumers, despite undercooked meat being identified as an important source of human infection.

Hepatitis E in humans is also caused by the consumption of undercooked or raw meat and despite 92.8% of pigs being found to have antibodies to the virus at slaughter, indicating infection at some point, only 1% had the potential to transmit infection to humans.

Next steps

Mr Armstrong said the supply chain needed to look at rewarding farmers for better controlling risks, but the benefits must cover the costs.

“The most cost-efficient controls or mechanisms to pass costs up the food chain need identifying, or ways to pass rewards down,” he added.