The potential use of chilling to control the growth ofEnterobacteriaceaeon porcine carcasses and the incidence ofE. coliO157:H7 in pigs

Abstract

Aims: To (i) monitor the presence of Enterobacteriaceae as indicators of faecal contamination on pig carcasses, (ii) examine the potential use of chilling as a critical control point (CCP) and establish its influence on pig carcass categorization by Decision 471/EC and (iii) determine the incidence of E. coli O157:H7 in pigs. Methods and Results: Porcine faecal samples and carcass swabs were collected before and after chilling at four Irish pig abattoirs and examined for Enterobacteriaceae and E. coli O157:H7. Chilling generally reduced Enterobacteriaceae counts on carcasses, but increases were also observed, particularly in one abattoir. E. coli O157:H7 was absent from carcasses before chilling, present on 0·21% after chilling and was recovered from 0·63% of faecal samples. All of the isolates were found to contain virulence genes associated with clinical illness in humans. Conclusions: The data show that overall chilling had the capacity to reduce the numbers of carcasses positive for the presence of Enterobacteriaceae. Significance and Impact of Study: The influence of chilling on the categorization of pig carcasses suggests that it has the potential to improve the numbers of acceptable carcasses and the process could be used as a CCP within a HACCP plan.

Shiga Toxigenic and Atypical EnteropathogenicEscherichia coliin the Feces and Carcasses of Slaughtered Pigs

“…These results were similar to the findings from studies conducted in France, Belgium, and Ireland using swine carcasses (Bouvet et al, 2001;Botteldoorn et al, 2003;Lenahan et al, 2009). However, the use of a more specific technique for O157:H7, such as immunomagnetic separation (IMS), may improve detection of this microorganism.…”

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

“…Other studies have noted a reduction in TVC's and Enterobacteriaceae counts on lamb (Biss & Hathaway, 1995;Gill & Jones, 1997), beef (McEvoy, Sheridan, Blair, & McDowell, 2004 and pork carcasses (Lenahan et al, 2009) as a result of chilling. Increases in counts after chilling were also observed on 58% of carcasses for TVC's and 26% for Enterobacteriaceae.…”

Antibacterial activity of decontamination treatments for pig carcasses

“…Published data indicate that under commercial conditions, chilling can result in increases, decreases or no changes of bacterial contamination, dependent on temperature, air speed, humidity, carcass spacing and duration (Bolton et al, 2002;Gill et al, 2000;Lenahan et al, 2009;Nesbakken et al, 2008;Pearce et al, 2004;Rahkio et al, 1992;Spescha et al, 2006;Yu et al, 1999). Spescha et al (2006) investigated the antibacterial efficacy of blast chilling and conventional chilling under commercial conditions.…”

“…Furthermore, several studies investigated the antibacterial efficacy of chilling procedures under commercial conditions without exact designation of process parameters (Bolton et al, 2002;Gill et al, 2000;Lenahan et al, 2009). Inconsistent effects ranging from moderate decreases to slight increases of the bacterial levels on pig carcasses were thereby observed.…”