Salmonella prevalence and microbiological contamination of pig carcasses and slaughterhouse environment

Abstract

In seven EC swine abattoirs Salmonella prevalence (ISO 6579/2002) and serotypes of 25 piglets, 61 finishing pigs (lymph nodes, colon content, carcass and liver surface) and slaughterhouse environments (scalding water, surfaces in contact with meat and not in contact with meat) were investigated. Moreover, aerobic colony count [total viable count (TVC); ISO 4833] and Enterobacteriaceae (ISO 21528-2) of piglets and finishing pigs’ carcasses were evaluated, and the results compared with EU process hygiene criteria (Reg. EC 2073/2005). Salmonella was not isolated in any of the piglets samples. Prevalence differed between slaughterhouses (P<0.5), and Salmonella was isolated from 39 of 244 samples of finishing slaughtered pigs (15.9%) and from 4 of 45 environmental samples (8.9%). In pig samples, carcasses showed the highest prevalence (18%) followed by colon content (14.8%), lymph nodes (13%) and liver (1.6%). S. Anatum was the most prevalent serotype (71.8%), followed by S. Derby (33.3%), S. Bredeney (5%) and S. Holcomb (2.5%). Between environmental samples, S. Anatum (50%), S. Bredeney and S. Derby (25%) were identified. Total viable mean counts (log10 CFU/cm2) of carcass surfaces ranged from 4.6 and 5.7 for piglets, and from 4.6 and 5.9 for finishing pigs, while Enterobacteriaceae ranged between 1.1 and 5 for piglets and between 2.1 and 5.3 for finishing pigs. These results were not in compliance with EU performance criteria. Total aerobic viable counts and Enterobacteriaceae mean levels of environmental samples appeared critical, particularly referred to surfaces in contact with meat (splitting equipment) and indicated an inadequate application of good manufacturing and hygiene practices during slaughtering and sanitisation.

Prevalence and associated risk factors of Salmonella spp. On the pork production chain in Córdoba, Argentina

“…To our knowledge, there are no official reported data about the prevalence of Salmonella at slaughterhouses or pork products at retail markets in the country, so this may be the first epidemiological study among the whole pork production chain in the region. When our results were compared with studies from other countries, the Salmonella prevalence at slaughterhouses was similar that observed in Vietnam (22%) but higher than reported in Naples (15.9%), Parma (10.9%) and Rio de Janeiro (10.5%) (Yokomo et al, 2016;Piras et al, 2014;Bonardi et al, 2013;Cabral et al, 2016). The Salmonella prevalence in pork sausage ("chorizo") at retail markets was consistent to other study in Brazil, with a similar pork production chain (26%) (Cabral et al, 2014).…”

Occurrence and traceability of Salmonella spp. in five Sardinian fermented sausage facilities

“…This result was expected as this serotype is well known to be adapted to pigs (Matiasovic et al ., 2014). In fact, it is one of the most common in slaughter pigs in Italy (Bonardi et al ., 2003 and 2016; Piras et al ., 2011 and 2014; Fois et al ., 2017; Pesciaroli et al ., 2017) and other European countries (Nollet et al ., 2004; Hauser et al ., 2011; Gomes-Neves et al ., 2012; Kerouanton et al ., 2013; Sanchez- Rodriguez et al ., 2018). Moreover, S .…”

Omissions in the disinfection of a craft-slaughterhouse

“…The results of the total number of bacteria (log CFU / cm2) obtained after disinfection of the hook and meat knife indicate that the professional veterinarian properly carried out all the disinfection phases, as well as the disinfection itself, since the total number of bacteria was significantly lower (p <0.01) during the course of all five weeks, in relation to the number of bacteria after disinfection by an unprofessional person. Properly conducted disinfection and replacement of knives during work are very important because studies have shown that the most common way of meat contamination is with dirty hands and dirty tools (Haileselassie et al, 2013;Piras at al., 2014;Abdalla et al, 2009;Svobodová et al, 2012;Gun et al, 2003). In the slaughterhouses the knives are washed in a traditional manner by rinsing with water at a temperature of 20˚-40˚C, followed by a brief immersion in a bath (sterilizer) in which the water temperature is below 82˚C (EC Regulation 853/2004).…”

“…It is concluded that the usual cleaning and disinfection of the lairage were not sufficient to eliminate this risk, whereas an improved procedure for cleaning and disinfection was still unsatisfactory. In the literature, most authors point to the fact that a significant reduction in the level of microorganisms in the slaughterhouses can be achieved only when effective sanitary washing with hot water is carried out prior to disinfection (Piras at al., 2014;McDowell et al, 2007;Rajkowski et al, 1998).…”

“…Boughton et al (2007) and Small et al (2007) reported that routine cleaning and washing of the lairage with cold water are not sufficient for the removal of pathogenic microorganisms. Total aerobic viable counts and Enterobacteriaceae (mean levels) from the samples was critical to surfaces in contact with meat (splitting equipment) and indicated an inadequate application of good manufacturing and hygiene practices during slaughtering and sanitization (Piras at al., 2014). Haileselassie et al (2013) reported that among bacterial contaminants of meat isolated in a study carried out at the municipality abattoir and butcher shops the predominant organisms included E. coli, S. aureus and B. cereus.…”