Enteric fever is primarily a septicemia caused by bacteria of the salmonella group. It is the common manifestation of infection with Salmonella typhi and S. paratyphi A, B, and C, which are highly adapted to human beings. Salmonella typhimurium, in contrast, affects all species of animals and is one of the most common causes of foodborne disease in humans. Most salmonella infections in farm animals are likely to be acquired from an animal of the same species, especially in the case of the host-adapted serovars. Salmonellae may survive for long periods in infected feces and slurry, where their survival is dependent on a number of factors, especially the climatic conditions. One important aspect is the persistence of salmonellae in animal accommodation after depopulation. Symptoms vary widely from sudden death in the acutely affected animals to symptomless carriers which excrete salmonella in their feces with no apparent signs of ill health.