482
edits
Changes
no edit summary
There are many different serotypes of [[Salmonella|''Salmonella'']].
== Introduction ==
All can produce disease BUT only a few commonly produce illness in UK.
There are many different serotypes of [[Salmonella|''Salmonella'']]. All can produce disease, but only a few commonly produce illness in UK. ''Salmonella'' poses a serious risk to man and is hence a '''zoonosis''' and a public health issue. Disease in man is mostly contracted from poultry or cattle. Reptiles are also healthy carriers of Salmonella and these may also infect humans that are in frequent contact with these animals.
''Salmonella'' poses a serious risk to man.
<br>
[[Salmonella|'''''Salmonella enteritidis''''']] and [[Salmonella|'''''Salmonella typhimurium''''']] are widespread in most species. [[Salmonella|''''' Salmonella dublin''''']] is a cause of disease in cattle and [[Salmonella|'''''Salmonella cholerae suis''''']] is prevalent in pigs and is usually septicaemic, although is now quite rare. [[Salmonella|'''''Salmonella montevideo''''']] causes disease in humans and animals from contaminated imported meat and bone meal.
<br>
Salmonellosis is NOT very common in the dog and cat, however, the horse is often a carrier. Stress may precipitate the disease, meaning Salmonellosis is seen often in veterinary hospitals.
<br>
Salmonella strains are often named after where they were first isolated. All strains can occur epizootically, enzootically and sporadically. The strains can all produce similar clinical signs. Infection is via the faecal- oral route and organisms penetrate enterocytes before crossing the mucosa and entering macrophages. After entering macrophages, organins may then either remain localised to the gut, or are carried round the body to cause disease. There are 2 main types of disease; '''septicaemic''' and '''enteric'''. Each outbreak causes only one type of disease. The type of disease is linked to serotype- some serotyopres produce septicaemia, whereas others remain localised in the gut.
<br>
Septicaemic salmonellosis is very dramatic and produces death quite suddenly.
== Septicaemic disease ==
[[Diarrhoea|diarrhoea]] is often not seen before death.
Septicaemic salmonellosis is very dramatic and produces death quite suddenly and [[Diarrhoea|diarrhoea]] is often not seen before death. This form of the disease is unusual in the very young and usually occurs post-weaning. This is around 6 to 9 months in calves and around 6 to 10 weeks in pigs.
This form of the disease is unusual in the very young.
<br>
The organism colonises bowel epithelium, where it affects the [[Peyer's Patches - Anatomy & Physiology|Peyers patches]]. It then invades macrophages, which enable it to invade across the epithelium to the submucosa. It may then either remain localised to submucosa, or spread to the lymph nodes and enter the circulation to become septicaemic. Animals may die at this stage (30%), but this depends on such factors as the infecting dose and strain. Is similar to septicaemic[[Escherichia coli|'' E. Coli'']].
<br>
== Clinical Signs ==
Animals suffer from pyrexia, and occasionally a little bit of [[Diarrhoea|diarrhoea]]. The skin is reddened diffusely and bruise-like dark purplish-red blotched may be seen. The intestines maay show mild catarrhal enteritis, becoming fibrinous lower down. The bowel is generally flaccid, reddened and filled with fluid. Ecchymotic and petechial haemorrhages are often see on the serosa and mucosa. There may also be enlarged, haemorrhagic mesenteric lymph nodes and excessive blood-tinged peritoneal fluid. The lungs are collapsed and frothy and the heart is often dilated with ecchymotic haemorrhages. The [[Liver - Anatomy & Physiology|liver]] and kidneys are also flabby and may have subcapsular haemorrhages and may contain small white foci of necrosis known as '''paratyphoid granulomas'''.
<br>
== Diagnosis ==
By culture of blood and from mesenteric lymph nodes (which are oedematous and red).
By culture of blood and from mesenteric lymph nodes (which are oedematous and red).
[[Category:Enteritis, Fibrinous/Haemorrhagic]][[Category:Enteritis,_Bacterial]]
[[Category:Enteritis, Fibrinous/Haemorrhagic]][[Category:Enteritis,_Bacterial]]
[[Category:Enteritis,_Ulcerative]]
[[Category:Enteritis,_Ulcerative]]
[[Category:Hepatitis,_Bacterial]][[Category:Intestinal Diseases - Cattle]][[Category:To_Do_-_Clinical]]
[[Category:Hepatitis,_Bacterial]][[Category:Intestinal Diseases - Cattle]][[Category:To_Do_-_Review]]