J4-7608 Control of contamination of poultry meat with campylobacters in slaughterhouse (Basic project ARRS)

Duration of the project:

1.3.2016 – 28.2.2019


University of Ljubljana,Veterinary Faculty
University of Ljubljana, Biotechnical Faculty
University of Primorska Faculty of Health Sciences
Perutnina Ptuj d.d.

Principal investigator / researcher:

prof. Matjaž Ocepek (SICRIS)

Project coordinator at UP FHS:

prof. Darja Barlič Maganja (SICRIS, ResearchGate)


Intestinal campylobacteriosis is the predominant bacterial zoonosis in humans in Europe and in other industrialized countries. Costs related to campylobacteriosis are estimated at ~2.4 billion €. The main cause of acute gastroenteritis is C. jejuni, commensal inhabitant of the intestinal microbiota of industrial poultry. The main source of human infection is poultry meat, contaminated with faeces during slaughtering, in combination with improper thermal processing and/or crosscontamination.

In Slovenia, thermotolerant campylobacters have been found in 7080% of investigated broiler flocks. The official contamination rate of broiler carcasses at the end of slaughtering is similar. In the scope of previously conducted research, we have demonstrated that the majority of contamination occurs before the entrance to the evisceration room, that is during stunning, scalding and plucking, and that the carcass contamination rate increases with the number of consecutive slaughter
batches. Consequently, we presume that it is possible to reduce contamination with campylobacters in this part of the slaughtering process and thus contribute to the safety of the final product. Even though campylobacters are highly sensitive to environmental conditions, they harbour special mechanisms of resistance and survival, including the adhesivity and biofilm forming ability, which contribute to persistence, survival and infection transmission. Alink has been suggested between epidemiological moleculargenetic background, the ability to survive outside the intestines and different mechanisms of resistance, including adhesivity and biofilm forming ability. Goals:
1) To study the dynamics of faecal carcass contamination at the preevisceration stage of the slaughtering process, namely with different combinations of Campylobacterpositive and negative slaughter batches and with different parameters of the slaughtering regime. Also, the contamination potential of individual isolates according to their genotype will be compared and the possible persistence determined.
2) To determine the reason(s) and critical points for the increasing Campylobacter contamination of carcasses with successive Campylobacterpositive slaughter batches.
3) To compare the isolates from different critical contamination points with the strains that persist on the equipment of slaughter line and determine their ability to survive in the slaughterhouse conditions. The ability for adhesion and formation of biofilms in addition to their resistance against biotic and abiotic factors will be analyzed, in conventional and alternative decontamination procedures. A possible connection of these characteristics with different Campylobacter genotypes will also be determined.
4) To study and evaluate the possibility or effects of the employment of alternative technological procedures for decontamination of carcasses on the slaughter line, with the use of neutral electrolyzing oxidative water (NEOW) at the selected points or phases of the slaughtering process.
5) To use digital PCR as one of the most contemporary molecular methods for identification and easier absolute quantification of campylobacters. Comparison with conventional C. jejuni c o l o n ycounting will assess the applicability of both methods for the quantification of campylobacters in complex samples from the
slaughterhouse environment.
6) To implement the nextgeneration sequencing (NGS) for typing of Campylobacter sp. The analysis of the whole genome or various genomic parts (like MLST segments) will be introduced for the selected strains, which will be typed by using the sequence data. NGS will be employed for the analysis of microbial communities that are present on the slaughter.
7) According to the obtained findings, improvements of the slaughtering process and implementation of adequate correction hygienic or technological measures for the reduction of faecal car cass contamination will be suggested.

»The authors acknowledge the project J4-7608 Control of contamination of poultry meat with campylobacters in slaughterhouse was finacially supported by the Slovenian Research Agency.«