A survey has updated knowledge on the level of Campylobacter and Salmonella on sheep meat.

The Food Standards Agency (FSA) funded survey looked at microbial contamination on sheep carcasses in abattoirs in England and Wales. This included culled ewes (sheep over 12-months old) and lamb (sheep under 12-months). It was run in conjunction with surveys funded by Defra and the PATH-SAFE research program. The last survey of microorganisms on sheep carcasses in England and Wales was in 2003.

Twelve of 132 abattoirs in England and Wales took part, covering 28 percent of the annual sheep slaughterhouse throughput. Abattoirs ranged in throughput from 3,000 to 756,000 sheep killed annually.

In total, 1,282 carcass swab samples were collected from February 2023 to January 2024. All samples were tested for the isolation and quantification of Salmonella, 366 were tested for Campylobacter, and 103 for Enterobacteriaceae; and E. coli.

E. coli and Enterobacteriaceae are typically carried in the intestines of most animals and are used as indicators of hygiene in the food industry.

Highlighted results

Salmonella was detected in seven carcass swabs. Five isolates were a sheep-adapted type with no confirmed association with human disease. The other two isolates were Salmonella Typhimurium, which causes human illnesses.

In the UK, 517 outbreak-associated cases of Salmonella were attributed to consumption of lamb and beef products between 2015 and 2020, mostly due to Salmonella Typhimurium. Almost 300 of these were from one outbreak.

Campylobacter contamination was detected on 76 carcasses. The predominant species was Campylobacter jejuni.

Prevalence of E. coli at 88.4 percent and Enterobacteriaceae at 75 percent was as expected in freshly slaughtered meat, with 81.6 percent and 84.5 percent of these samples, respectively, having low levels of contamination.

There were no significant differences in contamination rates between lambs and ewes.

Contamination on sheep carcasses was significantly lower than in cecal samples in the Defra study suggesting that slaughtering processes are effective in reducing contamination. Correct cooking as well as hygienic handling and preparation of sheep meat will reduce surface microbiological contamination further and minimize the risk for consumers.

However, high numbers of Campylobacter and indicator organisms on some carcasses suggested there was potential for improved practices at slaughter.

Data generated can help inform industry and government decision making, risk modeling and future microbiological risk assessments as part of trade negotiations.