Changes

Post mortem findings include; a shiny appearance of the serosa of the spiral colon, which will also be turgid and oedematous. Haemorrhage is sometimes seen. Characteristically in this disease, the small intestine is not affected. Fibrinous deposits are seen on the mucosa as the disease progresses and the mucosa underneath is eroded to expose blood vessels in lamina propria.

Post mortem findings include; a shiny appearance of the serosa of the spiral colon, which will also be turgid and oedematous. Haemorrhage is sometimes seen. Characteristically in this disease, the small intestine is not affected. Fibrinous deposits are seen on the mucosa as the disease progresses and the mucosa underneath is eroded to expose blood vessels in lamina propria.

Samples can be taken to perform silver stains to show organisms in the epithelium of the mucosa. The bacteria can also be cultured on blood agar with added antibiotics for at least 3 days - ''B. hyodysenteriae'' causes complete haemolysis whereas other spirochaetes cause partial haemolysis.  This is called a "strong beta" reaction, where complete beta hemolysis is visible, especially after removing a plug of agar.  This is called a ring phenomenon and is indicative of a pathogenic Brachyspira infection.   

Samples can be taken to perform silver stains to show organisms in the epithelium of the mucosa. The bacteria can also be cultured on blood agar with added antibiotics for at least 3 days at 42 degrees under anaerobic conditions.  The best samples are from colon of clinically ill pigs, rectal swabs are not sensitive. - ''B. hyodysenteriae'' causes complete haemolysis whereas other spirochaetes cause partial haemolysis.  This is called a "strong beta" reaction, where complete beta hemolysis is visible, especially after removing a plug of agar.  This is called a ring phenomenon and is indicative of a pathogenic Brachyspira infection.   

Immunofluorescence, DNA probes and biochemical tests can also be used though this is usually not cost effective. Serology using ELISA can be used on a herd basis as well as PCR, immunofluorescence or electron microscopy.

Immunofluorescence, DNA probes and biochemical tests can also be used though this is usually not cost effective. Serology using ELISA can be used on a herd basis as well as PCR, immunofluorescence or electron microscopy.  However, the gold standard and method of definitevely diagnosing Brachyspira is the presence of a strong beta hemolysis organisms isolated using selective media.

== Treatment and Control ==

== Treatment and Control ==