Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 3/14/2017
Publication Date: 5/30/2017
Citation: Bearson, S.M., Cai, G., Bearson, B.L. 2017. Transcriptional response of turkeys to MDR Salmonella enterica serovar heidelberg [abstract]. Microbe, American Society of Microbiology, June 1-5, 2017, New Orleans, Louisiana. Paper No. 880.
Technical Abstract: Food-producing animals such as swine, cattle and poultry are a major reservoir of the human foodborne pathogen Salmonella. While some Salmonella serovars can cause disease in food-producing animals, most serovars colonize these animals asymptomatically, resulting in the hosts becoming carriers and intermittent shedders of Salmonella. Poultry (turkey and chicken) are frequent carriers of Salmonella, and poultry products represent about 58 percent of the salmonellosis cases associated with products regulated by the Food Safety Inspection Service. In our search for control strategies to reduce Salmonella colonization and shedding in turkeys, we evaluated the transcriptional response of turkeys to the multidrug-resistant Salmonella enterica serovar Heidelberg (S. Heidelberg) strain associated with the 2011 multistate outbreak of Salmonella from ground turkey. This outbreak resulted in 136 confirmed cases of human foodborne disease (39 percent hospitalization rate) and the recall of 36 million pounds of ground turkey meat (one of the largest product recalls in history). MessengerRNA was isolated from blood collected on day 0 and 2 days post-inoculation (d.p.i.) by oral gavage with 1010 colony forming units of S. Heidelberg, and the mRNA was sequenced using an Illumina HiSeq 2500 (n equals 3-4 turkeys/time point). The S. Heidelberg challenge resulted in the differential expression of 100 turkey genes at 2 d.p.i. compared to pre-inoculation (false discovery rate less than 0.05; fold change greater than 1.5). A genome search of the domestic turkey Meleagris gallopavo revealed that ENSMGAG00000006516 (SCG3) was the most differentially expressed gene (repressed) and encodes secretogranin III with an unknown function in turkeys. Further analysis of the gene expression dataset is ongoing. Investigations and interventions in the animal reservoir are necessary to fully optimize control strategies against Salmonella and support food safety, especially as livestock production systems continue to increase in size and complexity, and antibiotic usage in feed becomes increasingly controversial.