Harnessing gut microbiota to mitigate Salmonella Dublin: Lessons from S. Typhimurium

The emerging cattle-adapted pathogen, Salmonella Dublin, threatens the global cattle industry by causing high mortality in calves and reduced production efficiency in cows. Due to limited therapeutic options, there is a need for novel interventions to mitigate S. Dublin. In the inflamed gut, Salmonella Typhimurium, and possibly S. Dublin, gain a metabolic advantage by utilizing niche nutrients during anaerobic respiration. S. Dublin invades intestinal epithelial cells using genes encoded by Salmonella pathogenicity island 1 (SPI-1), initiating systemic disease and chronic infection. Propionate, a microbial fermentation product, inhibits SPI-1 transcription, presenting an opportunity to prevent infection. Lactobacilli endogenous to the small intestine of calves may be leveraged to inhibit S. Dublin invasion and growth through propionate synthesis and nutrient blocking, respectively. Here, we discuss critical knowledge gaps of S. Dublin pathogenesis while offering data-driven insights for the development of sustainable microbial-based interventions to mitigate S. Dublin in cattle.