Prevalence of Campylobacter jejuni and Campylobacter coli in chicken hybrids with different growth rates, reared according to conventional and "free-range" production methods

Real-time monitoring of Salmonella enterica in free-range geese

Free-range geese were sampled longitudinally and Salmonella isolates characterized to reveal highly diverging colonization dynamics. One flock was intermittently colonized with one strain of Salmonella enterica serovar Enteritidis from 2 weeks of age, while in another, S. enterica serovar Mbandaka appeared after 9 weeks, without dissemination but with multiple serovars appearing at later stages.

Comparison of Campylobacter populations isolated from a free-range broiler flock before and after slaughter

Relatively little is known about the Campylobacter genotypes colonizing extensively reared broiler flocks and their survival through the slaughter process, despite the increasing demand for free-range and organic products by the consumer. Campylobacter isolates from a free-range boiler flock, sampled before and after slaughter, were genotyped by MLST (multilocus sequence typing) and sequence analysis of the flaA short variable region (SVR). The Campylobacter genotypes isolated before and after slaughter were diverse, with up to five sequence types (STs) (seven-locus allelic profiles resulting from MLST) identified per live bird, up to eight STs identified per carcass and 31 STs identified in all. The majority (72.0%) of isolates sampled from carcasses post-slaughter were indistinguishable from those isolated from the live flock before slaughter by ST and flaA SVR type, however, sampling 'on-farm' failed to capture all of the diversity seen post-slaughter. There were statistically significant increases in the genetic diversity of Campylobacter (p=0.005) and the proportion of C. coli (p=0.002), with some evidence for differential survival of genotypes contaminating the end product. C. coli genotypes isolated after slaughter were more similar to those from free-range and organic meat products sampled nationally, than from the live flock sampled previously. This study demonstrated the utility of MLST in detecting genetic diversity before and after the slaughter process.

Niche marketing production practices for beef cattle in the United States and prevalence of foodborne pathogens

Niche-marketed food products are rapidly gaining market share in today's society. Consumers are willing to pay premium prices for food perceived to be safer, healthier, more nutritious, and better tasting than conventional food. This review outlines typical production practices for niche-market beef production systems in the United States and compares prevalence estimates of foodborne pathogens in animals and produce from conventional and niche-market production systems. The two main niches for food animal production are organic and natural productions. Organic and natural beef productions are becoming increasingly popular and there is high consumer demand. Two major differences between conventional beef production systems and niche-market production systems (natural and organic) are in the use of antimicrobials and growth-promoting hormones. The impacts of these production systems on foodborne pathogens in beef cattle are variable and often data are nonexistent. Studies directly comparing conventional and niche-market production systems for dairy, swine, poultry, and produce have observed that the prevalence of foodborne pathogens was seldom statistically different between production systems, but when differences were observed, prevalence was typically greater for the niche-market production systems than the conventional production system. The published literature suggests that the perception of niche-marketed food products being safer and healthier for consumers with regard to foodborne pathogens may not be justified.