Timing and Delivery route effects of Cecal Microbiome transplants on Salmonella Typhimurium infections in Chickens

Abstract

BackgroundExposure to microbes early in life has long-lasting effects on microbial community structure and function of the microbiome. However, in commercial poultry settings chicks are reared as a single-age cohort with no exposure to adult birds which can have profound effects on microbiota development and subsequent pathogen challenge. Microbiota manipulation is a proven and promising strategy to help reduce pathogen load and transmission within broiler flocks. ResultsManipulation of the microbiota between 4 and 72 hours of hatch markedly reduces faecal shedding and colonisation with the foodborne pathogen Salmonella enterica serovar Typhimurium (ST4/74). Administration route has minimal effect on the protection conferred with fewer birds in transplant groups shown to shed ST4/74 in the faeces compared to PBS-gavaged control birds. Analysis of the microbiome following transplantation demonstrated that the relative abundance of the anti-inflammatory bacterium Faecalibacterium prausnitzii was significantly higher in CMT groups compared to PBS controls. The presence of F. prausnitzii was also shown to increase in PBS-challenged birds compared to unchallenged birds potentially indicating a role of this bacterium in limiting Salmonella infections. ConclusionsThis study highlights the efficacy of using microbiome transplants as a means to reduce colonisation and shedding of Salmonella in chickens. Effective protection can be conferred during the first few days of a chicks life regardless of time point and traditional hatchery delivery systems are sufficient to alter the microbiome and transfer donor material. Early microbiota intervention in chickens is a promising route of pathogen control in broiler flocks in the fight to control food-borne outbreaks in the human population.