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==Description==
 
==Description==
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Lamb dysentery is a peracute and fatal enterotoxaemia of young lambs caused by the beta and epsilon toxins of ''Clostridium perfringens'' type B. ''C. perfringens'' is a large, gram positive, anaerobic bacillus that is ubiquitous in the environment and commensalises the gastrointestinal tract of most mammals<sup>ivis</sup>. Five genotypes of ''Clostridium perfringens'' exist, named A-E, and all genotypes produce potent exotoxins. There are 12 exotoxins in total, some of which are lethal and others which are of minor significance<sup>lewis</sup>. These are produced as pro-toxins, and are converted to their toxic froms by digestive enzymes. The enterotoxaemias are a group of diseases caused by proliferation of ''C. perfringens'' in the lumen of the gastrointestinal tract and excessive production of exotoxin.
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Lamb dysentery is a peracute and fatal enterotoxaemia of young lambs caused by the beta and epsilon toxins of ''Clostridium perfringens'' type B. ''C. perfringens'' is a large, gram positive, anaerobic bacillus that is ubiquitous in the environment and commensalises the gastrointestinal tract of most mammals<sup>ivis</sup>. Five genotypes of ''Clostridium perfringens'' exist, named A-E, and all genotypes produce potent exotoxins. There are 12 exotoxins in total, some of which are lethal and others which are of minor significance<sup>lewis</sup>. These are produced as pro-toxins, and are converted to their toxic froms by digestive enzymes. The enterotoxaemias are a group of diseases caused by proliferation of ''C. perfringens'' in the lumen of the gastrointestinal tract and excessive production of exotoxin.
    
In healthy animals, there is a balance between multiplication of ''Clostridium perfringens'' and its passage in the faeces. This ensures that infection is maintained at a low level.  However, ''C. perfringens'' is saccharolytic and is therefore able to multiply rapidly when large quantities of fermentable carbohydrate are introduced to the anaerobic conditions of the abomasum and small intestine, leading to build-up of exotoxin. Gut statis, for example due to insufficient dietray fibre or a high gastrointestinal parasite burden, can also contribute to the accumulation of toxins.  
 
In healthy animals, there is a balance between multiplication of ''Clostridium perfringens'' and its passage in the faeces. This ensures that infection is maintained at a low level.  However, ''C. perfringens'' is saccharolytic and is therefore able to multiply rapidly when large quantities of fermentable carbohydrate are introduced to the anaerobic conditions of the abomasum and small intestine, leading to build-up of exotoxin. Gut statis, for example due to insufficient dietray fibre or a high gastrointestinal parasite burden, can also contribute to the accumulation of toxins.  
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Enterotoxaemia due to ''Clostridium  perfringens''  type B causes severe enteritis and dysentery with a high mortality in young lambs and also calves, pigs, and foals. The &beta; toxin highly necrotizing and lethal β toxin that is responsible for severe intestinal damage. This toxin is sensitive to proteolytic enzymes, and disease is associated with inhibition of proteolysis in the intestine. Sow colostrum, which contains a trypsin inhibitor, has been suggested as a factor in the susceptibility of young piglets. Type C also causes enterotoxemia in adult cattle, sheep, and goats. The diseases are listed below, categorized as to cause and host. C  perfringens  also has been associated with hemorrhagic enteritis in dogs. (See also  intestinal diseases in horses,  Intestinal Diseases in Horses and Foals: Introduction.)
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Enterotoxaemia due to ''Clostridium  perfringens''  type B causes severe enteritis and dysentery with a high mortality in young lambs and also calves, pigs, and foals. The &beta; toxin its produces is highly necrotising andis responsible for severe intestinal damage. &Epsilon; toxin also plays a part in pathogenesis.
Lamb dysentery: type B in lambs up to 3 wk of age
      
sargison: Laimb dysentery is aI peracute and fatal disease of youLng
 
sargison: Laimb dysentery is aI peracute and fatal disease of youLng
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extreme cases, losses of between 20 and 30 per cent of
 
extreme cases, losses of between 20 and 30 per cent of
 
animals in a flock have been reported.
 
animals in a flock have been reported.
Outbreaks of lamb dysentery are initially characterised
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by the sudden death of young lambs, but slower
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onset disease, manifesting as acute abdominal pain and
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non-specific nervous signs, is sometimes seen in older,
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two- to three-\veek-old lambs. Faeces may be semi-fluid
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and blood stained although, in most cases, they are normal
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due to the rapid course of the disease.
   
The diagnosis of lamb dysentery depenids on postmortemii
 
The diagnosis of lamb dysentery depenids on postmortemii
 
findings. At postmortem examination. localised
 
findings. At postmortem examination. localised
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