A Systematic Review Characterizing On-Farm Sources of Campylobacter spp. for Broiler Chickens

Abstract

Campylobacter and antimicrobial-resistant Campylobacter are frequently isolated from broiler chickens worldwide. In Canada, campylobacteriosis is the third leading cause of enteric disease and the regional emergence of ciprofloxacin-resistant Campylobacter in broiler chickens has raised a public health concern. This study aimed to identify, critically appraise, and synthesize literature on sources of Campylobacter in broilers at the farm level using systematic review methodology. Literature searches were conducted in January 2012 and included electronic searches in four bibliographic databases. Relevant studies in French or English (n = 95) conducted worldwide in any year and all study designs were included. Risk of Bias and GRADE criteria endorsed by the Cochrane collaboration was used to assess the internal validity of the study and overall confidence in the meta-analysis. The categories for on-farm sources were: broiler breeders/vertical transfer (number of studies = 32), animals (n = 57), humans (n = 26), environment (n = 54), and water (n = 63). Only three studies examined the antimicrobial resistance profiles of Campylobacter from these on-farm sources. Subgroups of data by source and outcome were analyzed using random effect meta-analysis. The highest risk for contaminating a new flock appears to be a contaminated barn environment due to insufficient cleaning and disinfection, insufficient downtime, and the presence of an adjacent broiler flock. Effective biosecurity enhancements from physical barriers to restricting human movement on the farm are recommended for consideration to enhance local on-farm food safety programs. Improved sampling procedures and standardized laboratory testing are needed for comparability across studies. Knowledge gaps that should be addressed include farm-level drug use and antimicrobial resistance information, further evaluation of the potential for vertical transfer, and improved genotyping methods to strengthen our understanding of Campylobacter epidemiology in broilers at the farm-level. This systematic review emphasizes the importance of improved industry-level and on-farm risk management strategies to reduce pre-harvest Campylobacter in broilers.

Ciprofloxacin-resistant Campylobacter in broiler chicken in Canada

“…The literature suggests that on-farm sources and operational factors could contribute to the spread of antimicrobial resistant Campylobacter. A systematic review of the literature suggests that antimicrobial resistant Campylobacter may be disseminated within a flock through the drinking water line and could spread across the farm through farm workers (via contaminated footwear) (15). Campylobacter has been reported to be spread by chicken catching crews that travel from farm to farm and then onto slaughter plants when birds were exposed to contaminated poultry equipment at transport (15).…”

“…A systematic review of the literature suggests that antimicrobial resistant Campylobacter may be disseminated within a flock through the drinking water line and could spread across the farm through farm workers (via contaminated footwear) (15). Campylobacter has been reported to be spread by chicken catching crews that travel from farm to farm and then onto slaughter plants when birds were exposed to contaminated poultry equipment at transport (15). The slaughter of chickens from Campylobacter-positive farms was associated with the contamination of chicken meat products (11,13,14).…”

Comparative analysis of antimicrobial resistance and genetic diversity of Campylobacter from broilers slaughtered in Poland

“…These microorganisms are a part of normal gastrointestinal microflora in many animals, especially birds (Epps et al, 2013). Chickens can be infected with the bacteria at a very high level without any clinical symptoms and Campylobacter is frequently isolated from the caecal microflora (Agunos et al, 2014;Lindmark et al, 2009). Intestinal content is therefore suspected to be the main source of broiler carcass contamination at slaughter (Kudirkiene et al, 2011).…”

“…Additionally, knowledge about Campylobacter antimicrobial resistance at different levels of poultry production is important for development of effective control strategies. Several studies have been conducted to investigate the prevalence and Campylobacter antimicrobial susceptibility patterns and most of them reported the emergence of resistant strains, especially to quinolones (Agunos et al, 2014;Cardinale et al, 2006;Fraqueza et al, 2014;Messad et al, 2014;Nobile et al, 2013;Wimalarathna et al, 2013).…”

The Relationship between Human Campylobacteriosis and Broilers

“…19,22,23 Farms with poorer biosecurity measures have been linked with having broilers with more strains of Campylobacter. 24 There is limited knowledge about how Campylobacter persists in broiler litter and faeces.…”