Microbial Contamination Occurring on Lamb Carcasses Processed in the United States

Abstract

Lamb carcasses (n = 5,042) were sampled from six major lamb packing facilities in the United States over 3 days during each of two visits (fall or winter, October through February; spring, March through June) in order to develop a microbiological baseline for the incidence (presence or absence) of Salmonella spp. and for populations of Escherichia coli after 24 h of chilling following slaughter. Samples also were analyzed for aerobic plate counts (APC) and total coliform counts (TCC). Additionally, incidence (presence or absence) of Campylobacter jejuni/coli on lamb carcasses (n = 2,226) was, determined during the slaughtering process and in the cooler. All samples were obtained by sponge-sampling the muscle-adipose tissue surface of the flank, breast, and leg of lamb carcasses (100 cm2 per site; 300 cm2 total). Incidence of Salmonella spp. in samples collected from chilled carcasses was 1.5% for both seasons combined, with 1.9% and 1.2% of fall or winter and spring samples being positive, respectively. Mean (log CFU/cm2) APC, TCC, and E. coli counts (ECC) on chilled lamb carcasses across both seasons were 4.42, 1.18, and 0.70, respectively. APC were lower (P < 0.05) in samples collected in the spring versus fall or winter, while TCC were higher in samples collected in the spring. There was no difference (P > 0.05) between ECC from samples collected in the spring versus winter. Only 7 out of 2,226 total samples (0.3%) tested positive for C. jejuni/coli, across all sampling sites. These results should be useful to the lamb industry and regulatory authorities as new regulatory requirements for meat inspection become effective.

E. coli O157:H7 and Salmonella Species: Public Health Importance and Microbial Safety in Beef at Selected Slaughter Houses and Retail Shops in Eastern Ethiopia

“…Lower level of aerobic plate count in this study was much lower than previous studies [2,[35][36][37]. However, the microbial contamination level of slaughterhouse and retail shops were higher as compared to reports from developed countries and our results do not conform to EU specifications [38,39].…”

Assessment of lamb carcass hygiene before and after chilling at five Irish abattoirs

“…A low prevalence of the pathogen was found on fleece (0.25%) and in faeces (0.25%). Previous studies have reported Salmonella on 4.3% of pre-evisceration lamb carcasses (Kalchayanand et al, 2007) and 1.5% on chilled carcasses (Duffy et al, 2001). The pathogen has been detected in 0.1-11% of sheep faeces (Davies et al, 2004;Milnes et al, 2008;Zweifel, Zychowska, & Stephan, 2004) and on 7.8-14.4% of fleece (Kalchayanand et al, 2007;Small et al, 2002).…”

“…In the latter studies it was noted that bacterial distribution on carcasses was not uniform and the carcasses selected for sampling could have a big influence on the TVC's and Enterobacteriaceae counts recorded. Australia and the US have successfully incorporated chilling into a HACCP plan (Duffy et al, 2001;Sumner et al, 2003). In Australia, three baseline studies over 11 years showed an improvement in the microbiological quality of beef carcasses and this was attributed in part to investment in chilling systems (Philips, Jordan, Morris, Jenson, & Sumner, 2006).…”

Human campylobacteriosis: a challenge for the veterinary profession

“…In metropolitan Washington, DC, for example, 130 of 184 (71%) packages of chicken sold at retail outlets contained C jejuni or C coli, followed by 4% of 172 turkey packages and < 2% of pork and beef packages. 42 Another US study 89 of more than 2,000 lamb carcasses from 6 large processing plants showed that < 1% were contaminated with C jejuni or C coli. In an English study 3 of nearly 500 retail specimens, chicken meat had the highest contamination rate (83%); however, the majority of lamb liver (73%), pork liver (72%), and beef liver (54%) was also contaminated.…”