Beneficial Cecal Microbiome Modulation in Turkeys Exposed to Probiotics and Vaccine After Multidrug-Resistant Salmonella Heidelberg Challenge

Abstract

Salmonella Heidelberg (SH) is a major serotype of foodborne Salmonella associated with turkeys. Understanding the effect of antibiotic alternatives (AAs) on the cecal microbiome of turkeys challenged with Salmonella could inform the development of microbiome-based strategies on farms. This study examined the effects of multiple AAs, such as probiotics, Lactobacillus and Propionibacterium, and a Salmonella Typhimurium vaccine, on the turkey cecal microbiome exposed to multidrug-resistant (MDR) SH. Microbial DNA was extracted from the cecal contents of 12-week-old commercial turkeys grown in five treatments for shotgun metagenomic sequencing and analysis: NC—Negative Control; PC—Salmonella Control; LAB—Lactobacillus treatment; PF—P. freudenreichii treatment; and VAC—vaccine treatment. Except for the NC, turkeys were challenged with MDR SH (108 CFU/turkey) on the 11th week. Differential abundance tests at the species level found that all AA treatments resulted in an increased abundance of multiple lactic acid-producing bacteria in the cecum compared to PC. In addition, multiple metabolic pathways were differentially abundant in AA treatments compared to PC. This study highlights the importance of AA strategies producing an increased abundance of lactic acid bacteria and critical metabolic pathways, indicating the potential of AAs to improve the gut health of turkeys during the Salmonella challenge.