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| − | *Swine dysentery gives rise to fibrinous/ haemorrhagic enteritis.
| + | #redirect[[Brachyspira hyodysenteriae]] |
| − | *A quite common and important disease.
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| − | *The disease is caused by [[Brachyspira hyodysenteriae|''Brachyspira hyodysenteriae'']].
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| − | **Is not seen in gnotobiotic animals - other enteric pathogens such as [[Fusobacterium necrophorum|''Fusobacterium'']] or [[Bacteroides|''Bacteroides'']] may therefore also be required in order to produce disease.
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| − | *The disease is NOT systemic.
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| − | **Localised to the [[Large Intestine - Anatomy & Physiology|large intestine]]- in particular, the spiral [[Colon - Anatomy & Physiology|colon]].
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| − | *Swine dysentery is spread by the faeco-oral route, and is carried by pigs and rodents.
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| − | === Clinical ===
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| − | *Affects post weaning pigs at approximately 4 months of age.
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| − | *White scour becomes a liquid dirty red / brown scour with a foul smell.
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| − | **Contains poorly digested focal shreds of mucosa and fibrin strands.
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| − | ***'''Mucoid covered faeces'''.
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| − | *There are three outcomes to infection; the animal may:
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| − | **Die
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| − | **There is a morbidity up to 90% in the herd, with up to 50% mortality.
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| − | **Recover
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| − | **Become chronically infected.
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| − | *Symptoms are due to loss of absorption in [[Colon - Anatomy & Physiology|colon]].
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| − | **The [[Colon - Anatomy & Physiology|colon]] is normally a key site of absorption for water and electrolytes in the pig.
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| − | === Pathology ===
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| − | *The serosa of the spiral [[Colon - Anatomy & Physiology|colon]] may appear shiny from the outside.
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| − | **Is turgid and oedematous.
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| − | **In severe cases, haemorrhage may be seen.
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| − | *The [[Small Intestine Overview - Anatomy & Physiology|small intestine]] NOT affected.
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| − | *Fibrinous deposits are seen on the mucosa as the disease progresses.
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| − | **The mucosa underneath is eroded to expose blood vessels in lamina propria.
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| − | ***Accounts for the bleeding.
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| − | *Animals often recover, but have a low feed conversion ratio for sometime.
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| − | === Diagnosis ===
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| − | *Silver stains show organisms in the epithelium of the mucosa.
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| − | *Clinical signs
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| − | **''B. hyodysenteriae'' causes dysentry in weaned pigs 6-12 weeks old; pigs lose condition and become emaciated; appetite is decreased; large amount of mucous may be present in the faeces; low mortality; poor feed conversion ratio
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| − | *Diagnosis
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| − | **History, clinical signs and gross pathology
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| − | **Anaerobic culture on blood agar with added antibiotics for at least 3 days
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| − | **''B. hyodysenteriae'' causes complete haemolysis whereas other spirochaetes cause partial haemolysis
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| − | **Immunofluorescence, DNA probes and biochemical tests
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| − | **Serology using ELISA can be used on a herd basis
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| − | **PCR
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| − | *Also by immunofluorescence or electron microscopy.
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| − | [[Category:Enteritis,_Bacterial]] [[Category:Enteritis,_Fibrinous/Haemorrhagic]] [[Category:Intestinal_Diseases_-_Pig]] [[Category:To_Do_-_Kate]]
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