Campylobacter spp. in Broiler Flocks at Farm Level and the Potential for Cross‐Contamination During Slaughter

Abstract

Screening of broiler flocks for their Campylobacter carriage on farm level and consequently the spread of Campylobacter spp. during slaughtering can help to identify hygiene control points. Therefore, between December 2001 and August 2002 in total 51 broiler flocks from three farms of different geographical regions in Germany were analysed for thermophilic Campylobacter. Campylobacter spp. were isolated from 45% of the broiler flocks examined. Subsequently, 1101 samples were taken from 22 flocks during different stages of processing. Samples were collected from: transport crates before and after cleaning/disinfection, evisceration, post-scalded and post-chilled carcasses and endproducts. Additionally, 45 selected Campylobacter isolates of droppings were genotyped by pulsed-field gel electrophoresis (PFGE). Campylobacter carriage of flocks showed seasonal variation, with the highest contamination rate during the period of June to August. No evidence was found for a horizontal transmission from one broiler flock to the next via a persistent house-contamination. In each positive flock, one to three different genotypes were found. One or two clones dominated isolations obtained from the farm level. The fact that in different flocks indistinguishable isolates of clonal origin were detected during the same rearing period suggested a transmission between the broiler flocks or an intermittent common external source. In one case, isolates of clonal origin were detected in various farms during different rearing periods. Sampling during processing confirmed that the entrance of a positive flock resulted in contamination of the abattoir environment. Campylobacter spp. were isolated from all sampling stages along the processing line, with a percentage of 91.1-100 of isolates at different stages of slaughtering.

Poultry flocks as a source of Campylobacter contamination of broiler carcasses

“…The Campylobacter-infected flocks may be a source of these bacteria for the corresponding carcasses, although the presence of the same bacterial species in the paired samples (flock -carcass) might also be due to cross-contamination during a slaughter process. These kind of transmission was also confirmed by other authors (Allen et al 2007, Ellerbroek et al 2010. Furthermore, the identification of other Campylobacter species on carcasses than those in the original flocks may also suggest a different contamination sources and routes.…”

“…These findings should be further tested using methods for molecular characterization of the Campylobacter isolates of the same species (Normand et al 2008). During processing, the spread of Campylobacter and the cross-contamination of broiler carcasses by the bacteria present in the intestinal content may create a hygiene problem (Ellerbroek et al 2010). The results of the present and other studies suggest that control mechanisms at slaughterhouses may be more promising than countermeasures being applied at the farm level only; however, the complete elimination of Campylobacter during processing is probably not possible (Allen et al 2007, Reich et al 2008.…”

Poultry as a Host for the Zoonotic PathogenCampylobacter jejuni

“…This study also indicated that bovine fecal Campylobacter strains can colonize chickens, which was confirmed later on by Patriarchi et al (2011). On a German farm, indistinguishable isolates of clonal origin were found in different flocks during the same rearing period (Ellerbroek et al 2010). This suggests that Campylobacter strains might be transmitted from one broiler flock to another or might point toward a common external source infecting multiple broiler flocks at the same farm.…”

“…Also, the time of year clearly has an influence. In Germany and the United Kingom, the risk for broilers to become colonized with Campylobacter is highest during the summer months (McDowell et al 2008, EllisIversen et al 2009, Ellerbroek et al 2010, Jorgensen et al 2011) and a coincident seasonality of infections in chickens and humans has been shown (Meldrum et al 2005). In the EUwide baseline survey on Campylobacter in broiler batches in 2008, batches were most likely to be found Campylobacter colonized in the third quarter ( July-September) of the year (EFSA 2010b).…”

“…Indeed, carcasses can also become contaminated by crosscontamination of Campylobacter between birds within a flock and between flocks slaughtered successively (Herman et al 2003, Rosenquist et al 2003, Rasschaert et al 2006 and even between flocks slaughtered in the same area, as evidenced in Quebec by Normand et al (2008). Campylobacter-colonized flocks contaminate the abattoir environment upon entering the room and as a consequence Campylobacter can be isolated at all stages of the processing line (Ellerbroek et al 2010). C. jejuni is able to survive overnight on these processing equipment surfaces, even after cleaning and disinfection (Peyrat et al 2008).…”