The prevalence of fecal Salmonella and anti-microbial Salmonella is lower in certified-organic broiler chickens than in chickens that are conventionally raised, according to a study recently published in the journal Foodborne Pathogens and Disease. 

The study was conducted by scientists at the University of Georgia in collaboration with scientists at Ohio State University and North Carolina State University. The authors point out in the introduction that:

[a]ccording to the Centers for Disease Control and Prevention (CDC), the incidence of Salmonella (i.e., 16.2 cases per 100,000 population/year) was the least improved of all foodborne pathogens in terms of achieving national health objective targets for Healthy People 2010. Poultry remains an important vehicle of Salmonella transmission to humans, occurring mainly via contaminated meat.

That statistic, coupled with the fact that poultry is the fastest growing meat product within the U.S. organic market, prompted scientists to compare the incidence of Salmonella in organic and conventional farming operations. The authors noted that “in consumers’ minds, organic foods appear to be a safer alternative to conventional poultry.” In performing this study, they wanted to determine whether that perception had any scientific basis.

Samples for the study were collected from one poultry company in North Carolina that maintains both USDA-certified organic and conventional broiler farms. In total, the team collected 700 samples (300 organic and 400 conventional), including floor droppings, feed samples, and drinking water. After analyzing the samples, scientists found that:

[t]he overall prevalence of Salmonella across all farms, sample types, and age group was 4.3% (13/300) in organic broiler farms compared to 28.8% (115/400) in conventional broiler farms.

The study also revealed significant findings regarding anti-microbial resistant Salmonella. The authors reported:

The overall prevalence of individual and multidrug anti-microbial resistance was higher in Salmonella isolates from conventional broiler farms than in those from organic broiler farms. Multidrug resistance was more frequent in Salmonella isolates from conventional broiler farms (55.2%) compared with organic farms (41.6%).


Thirty-six percent of conventional and 25 percent of organic Salmonella samples were found to be resistant to streptomycin. No organic samples and 39.7 percent of conventional samples had multidrug resistance to six antimicrobial agents: ampicillin-streptomycin-amoxicillin/clavulanic acid-cephalothin-ceftiofur-cefoxitin.

The study’s authors concluded by stating the need for further study of the presence of Salmonella in multiple large-scale certified-organic farming operations; however, the study provides useful information for all consumers concerned about food safety.