Changes

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.  

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 β toxin its produces is highly necrotising andis responsible for severe intestinal damage. Ε toxin also plays a part in pathogenesis.

Enterotoxaemia due to ''Clostridium  perfringens''  type B causes severe enteritis and dysentery with a high mortality in young lambs (lamb dysentery), but also in calves, pigs, and foals. The β toxin it produces is highly necrotising and is responsible for severe intestinal damage. Ε toxin also plays a part in pathogenesis. The incidence of lamb dysentery declined over the past 20 years or so, due to the widespread use of clostridial vaccins^sargison, but the condition is now becoming a problem again as complacency reduces flocks vaccinating for the disease. Outbreaks of lamb dysentery typically occur during cold,  wet lambing periods when lambing ewes are confined to small areas of shelter which rapidly become unhygienic. Most cases are seen in stronger, single lambs^sargison, because these animals consume the largest quantities of milk which functions as a growth medium for ''C. perfringens''. In extreme cases, 20-30% of lambs can be lost to lamb dysentery.

 

sargison: Laimb dysentery is aI peracute and fatal disease of youLng

i'ridiiio peJri-ingens type B. Over the past 20 years, the

disease had become rai-e due to the svidespread LIse of

clostr-idial xvaccines. Howverer, lamb dysenltery is becom-ing a conimon problem again due to reductions in ewe

vaccinations in many flocks. Affected lambs are usually

days old. The majority of cases are characterised by the

had been consuming the largest quantities of milk.

Outbreaks of lamb dysentery can occur during cold and

wvet springs wvhen lambing ewes are confined to small

sheltered areas and conditions become unhygienic. In

extreme cases, losses of between 20 and 30 per cent of

animals in a flock have been reported.

==Signalment==

==Signalment==