30 bytes added ,  20:01, 8 February 2008
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***This causes irreversible activation of adenylate cyclase in target cells
 
***This causes irreversible activation of adenylate cyclase in target cells
 
***This raises the cAMP level and causes hypersecretion of water and chloride ions into the lumen of the small intestine and inhibits reabsorption of sodium
 
***This raises the cAMP level and causes hypersecretion of water and chloride ions into the lumen of the small intestine and inhibits reabsorption of sodium
 +
***ST activates guanylate cyclase in enteric epithelial cells, stimulating fluid secretion
 
**Clinical signs:
 
**Clinical signs:
 
***The gut becomes distended with fluid and a [[Intestines - diarrhoea#Secretory Diarrhoeas|secretory diarrhoea]] which lasts several days results
 
***The gut becomes distended with fluid and a [[Intestines - diarrhoea#Secretory Diarrhoeas|secretory diarrhoea]] which lasts several days results
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***Parenteral vaccination of pigs and cattle protects offspring from scours via antibody production in the colostrum (passive immunity)
 
***Parenteral vaccination of pigs and cattle protects offspring from scours via antibody production in the colostrum (passive immunity)
 
***ST is not immunogenic; it is small, with only 19 amino acids
 
***ST is not immunogenic; it is small, with only 19 amino acids
***ST activates guanylate cyclase in enteric epithelial cells, stimulating fluid secretion
   
*Enteropathogenic ''E. coli'' (EPEC):
 
*Enteropathogenic ''E. coli'' (EPEC):
 
**Possess ''E. coli'' adherence factor plasmid
 
**Possess ''E. coli'' adherence factor plasmid
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**Cause attching and effacing lesions in the gut, with necrosis of enterocytes and stunting and fusion of villi
 
**Cause attching and effacing lesions in the gut, with necrosis of enterocytes and stunting and fusion of villi
 
*Enteroinvasive ''E. coli'':
 
*Enteroinvasive ''E. coli'':
 +
**Bacteraemia and septicaemia
 
**Dysentry-like strains
 
**Dysentry-like strains
 
**Invade epithelial cells by inducing endocytosis  
 
**Invade epithelial cells by inducing endocytosis  
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