Salmonella is a ubiquitous organism that is found everywhere in the environment. It is also resilient, with the ability to colonize and survive in any organism, from plants to insects to animals. There are thousands of Salmonella strains, but only a handful that will cause severe disease in pigs. Two of the most common types are Salmonella Typhimurium and Salmonella Choleraesuis.
Salmonella can present in both clinical and subclinical forms. Signs of clinical salmonellosis include diarrhea and septicemia. Subclinical signs are harder to identify, and can include weight loss, decreased appetite and poor feed conversion, leading to poor performance.