Occurrence of thermotolerant Campylobacter spp. at different stages of the poultry meat supply chain in Argentina

Abstract

AIMS: The objectives of this study were to investigate the occurrence and concentration of thermotolerant Campylobacter spp. at different stages of the poultry meat supply chain in Argentina.

METHODS: Three integrated poultry companies were sampled. Each supply chain was considered at different stages from the reproductive farm to chicken meat at a retail market. The stages sampled were: (a) hens from breeder flocks, (b) eggs in the incubator, (c) broiler chickens in flocks (aged <1 week and >5 weeks), (d) chickens at a slaughterhouse, and (e) chicken meat at a retail market. The chickens sampled along each supply chain were in the same batch. Samples collected were: (a) cloacal samples from hens and chickens on the farms, (b) fertile eggs, (c) feed, water and litter from flocks, (d) chicken carcasses from the slaughterhouse and retail market, and (e) caeca and livers from the slaughterhouse. Samples obtained were examined for Campylobacter spp. The isolates were biotyped and the genus and species identified by PCR. Campylobacter spp. on chicken carcasses at slaughterhouse and retail market were enumerated.

RESULTS: The highest proportions of Campylobacter positive samples were observed in carcasses at retail (25/30, 83.3%) and faecal samples from breeding hens (27/45, 60.0%). Only 3.3% (3/90) samples collected from broiler chickens aged <1 week were positive, but the percentage of positive samples had risen to 28.9% (26/90) by the end of the rearing period. The proportions of Campylobacter positive carcasses and caecal contents at the slaughterhouse were both 33.3% (10 of 30 samples each). The concentration of Campylobacter contamination observed on carcasses at retail markets ranged from no bacteria/carcass to 3.71 log₁₀ cfu/carcass.

CONCLUSIONS: The data obtained provide essential information for future quantitative risk assessments aiming to estimate the probability of a person contracting campylobacteriosis following consumption of broiler meat in Argentina.

CLINICAL RELEVANCE: The proportions of Campylobacter-positive samples found in this preliminary study indicate that a large proportion of the cases of human gastroenteritis in Argentina may be due to this pathogen. Human cases of gastroenteritis should be studied in greater detail and measures should be developed to reduce the proportion of poultry products that are contaminated by Campylobacter species.

KEY WORDS:

• Campylobacter spp.
• chickens
• zoonosis
• farm-to-fork
• poultry production
• food safety
• biotype

Acknowledgments

This study was funded by the AgenciaNacional de PromociónCientífica y Tecnológica (Argentina), Project PICTO CIN II 2010-0161. Lorena P. Soto is a postdoctoral fellow and María V. Zbrun is a doctoral fellow from the ConsejoNacional de InvestigacionesCientíficas y Técnicas (CONICET, Argentina). The authors gratefully acknowledge the participating broiler producers for allowing us to visit their farms. We also thank Dr. Horacio Terzolo and Alejandra Velilla from the National Institute of Agricultural Technology-EEA Balcarce (Argentina) for their assistance and cooperation in the training of our working group in bacteriological techniques of isolation and characterisation of thermophilic Campylobacter. The skilled technical assistance of Dr. Francisco Bongiovanni is gratefully acknowledged.