Equine salmonellosis

Sa？etak Equine salmonellosis is caused by various serovars of the Gram-negative bacteria Salmonella enterica subsp. enterica. Clinical signs of salmonellosis depend on the infective serovar and many factors influencing host susceptibility. The host specific serovar Salmonella abortusequi causes abortion at a later stage of pregnancy or, more rarely, orchitis and septicemia, osteomyelitis and arthritis in foals. Other host nonspecific serovars cause intestinal or systemic infections. Salmonella sp. infects a variety of animals and also humans. Many animal species, predominantly birds and rodents, are often salmonella reservoirs and excrete the bacteria in the environment. Horses become infected by ingesting Salmonella from many sources in the environment, primarily food and water contaminated by bacteria or by the carcasses of infected animals. Salmonella infection in horses may be subclinical or manifest as mild febrile disease, enterocolitis or septicaemia. The most common clinical findings are diarrhoea, fever, colic and leukopenia. The disease is confirmed by isolation of bacteria from the faeces, and the treatment and prognosis depend on the clinical form of the disease. Prevention of equine salmonellosis is hampered by the presence of numerous sources of infection in the environment. However, in the case of illness, the spread to other horses can be prevented by isolation of the infected animal and disinfection of the contaminated environment. Factors contributing to the excretion of Salmonella bacteria and/or the development of clinical form of disease in inapparently infected horses (stress, change in feeding behaviour, antimicrobial therapy, surgical procedures) are often present in hospitalized animals, which should therefore be considered as potential sources of infection for other animals and humans