Difference between revisions of "Swine Dysentery"

From WikiVet English
Jump to navigation Jump to search
(Redirected page to Brachyspira hyodysenteriae)
(4 intermediate revisions by one other user not shown)
Line 1: Line 1:
−
#redirect[[Brachyspira hyodysenteriae]]
+
* Swine dysentery gives rise to fibrinous/ haemorrhagic enteritis.
 +
* A quite common and important disease.
 +
* The disease is caused by [[Brachyspira hyodysenteriae|''Brachyspira hyodysenteriae'']].
 +
** 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.
 +
* The disease is NOT systemic.
 +
** Localised to the [[Large Intestine - Anatomy & Physiology|large intestine]]- in particular, the spiral [[Colon - Anatomy & Physiology|colon]].
 +
* Swine dysentery is spread by the faeco-oral route, and is carried by pigs and rodents.
 +
 
 +
===Clinical===
 +
 
 +
* Affects post weaning pigs at approximately 4 months of age.
 +
* White scour becomes a liquid dirty red / brown scour with a foul smell.
 +
** Contains poorly digested focal shreds of mucosa and fibrin strands.
 +
*** '''Mucoid covered faeces'''.
 +
* There are three outcomes to infection; the animal may:
 +
** Die
 +
** There is a morbidity up to 90% in the herd, with up to 50% mortality.
 +
** Recover
 +
** Become chronically infected.
 +
* Symptoms are due to loss of absorption in [[Colon - Anatomy & Physiology|colon]].
 +
** The [[Colon - Anatomy & Physiology|colon]] is normally a key site of absorption for water and electrolytes in the pig.
 +
 
 +
===Pathology===
 +
 
 +
* The serosa of the spiral [[Colon - Anatomy & Physiology|colon]] may appear shiny from the outside. 
 +
** Is turgid and oedematous.
 +
** In severe cases, haemorrhage may be seen. 
 +
* The [[Small Intestine Overview - Anatomy & Physiology|small intestine]] NOT affected. 
 +
* Fibrinous deposits are seen on the mucosa as the disease progresses. 
 +
** The mucosa underneath is eroded to expose blood vessels in lamina propria.
 +
*** Accounts for the bleeding.
 +
* Animals often recover, but have a low feed conversion ratio for sometime.
 +
 
 +
===Diagnosis===
 +
 
 +
* Silver stains show organisms in the epithelium of the mucosa.
 +
*Clinical signs
 +
**''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
 +
*Diagnosis
 +
**History, clinical signs and gross pathology
 +
**Anaerobic culture on blood agar with added antibiotics for at least 3 days
 +
**''B. hyodysenteriae'' causes complete haemolysis whereas other spirochaetes cause partial haemolysis
 +
**Immunofluorescence, DNA probes and biochemical tests
 +
**Serology using ELISA can be used on a herd basis
 +
**PCR
 +
 
 +
* Also by immunofluorescence or electron microscopy.[[Category:Enteritis,_Bacterial]][[Category:Enteritis,_Fibrinous/Haemorrhagic]][[Category:Intestinal Diseases - Pig]]
 +
[[Category:To_Do_-_Clinical]]

Revision as of 19:12, 17 January 2011

  • Swine dysentery gives rise to fibrinous/ haemorrhagic enteritis.
  • A quite common and important disease.
  • The disease is caused by Brachyspira hyodysenteriae.
    • Is not seen in gnotobiotic animals - other enteric pathogens such as Fusobacterium or Bacteroides may therefore also be required in order to produce disease.
  • The disease is NOT systemic.
  • Swine dysentery is spread by the faeco-oral route, and is carried by pigs and rodents.

Clinical

  • Affects post weaning pigs at approximately 4 months of age.
  • White scour becomes a liquid dirty red / brown scour with a foul smell.
    • Contains poorly digested focal shreds of mucosa and fibrin strands.
      • Mucoid covered faeces.
  • There are three outcomes to infection; the animal may:
    • Die
    • There is a morbidity up to 90% in the herd, with up to 50% mortality.
    • Recover
    • Become chronically infected.
  • Symptoms are due to loss of absorption in colon.
    • The colon is normally a key site of absorption for water and electrolytes in the pig.

Pathology

  • The serosa of the spiral colon may appear shiny from the outside.
    • Is turgid and oedematous.
    • In severe cases, haemorrhage may be seen.
  • The small intestine NOT affected.
  • Fibrinous deposits are seen on the mucosa as the disease progresses.
    • The mucosa underneath is eroded to expose blood vessels in lamina propria.
      • Accounts for the bleeding.
  • Animals often recover, but have a low feed conversion ratio for sometime.

Diagnosis

  • Silver stains show organisms in the epithelium of the mucosa.
  • Clinical signs
    • 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
  • Diagnosis
    • History, clinical signs and gross pathology
    • Anaerobic culture on blood agar with added antibiotics for at least 3 days
    • B. hyodysenteriae causes complete haemolysis whereas other spirochaetes cause partial haemolysis
    • Immunofluorescence, DNA probes and biochemical tests
    • Serology using ELISA can be used on a herd basis
    • PCR
  • Also by immunofluorescence or electron microscopy.
Retrieved from "https://en.wikivet.net/index.php?title=Swine_Dysentery&oldid=105122"