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Feeding behaviour can also be affected. Individual cows may show inappetance for 24-48h, with no other clinical signs and spontaneous resolution. Animals can also be seen to "drop the cud" while ruminating, and feed efficiency is reduced. This reduced efficiency may not be noticed in the field situation, but has been demonstrated experimentally and is associated with the passage of undigested food in the faeces.  
 
Feeding behaviour can also be affected. Individual cows may show inappetance for 24-48h, with no other clinical signs and spontaneous resolution. Animals can also be seen to "drop the cud" while ruminating, and feed efficiency is reduced. This reduced efficiency may not be noticed in the field situation, but has been demonstrated experimentally and is associated with the passage of undigested food in the faeces.  
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SARA can impact production parameters.
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SARA can impact production parameters. Milk yield is lowered, although on farms where subacute rumenal acidosis is an ongoing, chronic problem, this may not be recognised. Milk butterfat levels are also reduced, which may be due to two factors. Firstly, milk fat is produced from acetate and butyrate, which in turn are produced from fibre in the diet. Dietary fibre is often reduced in SARA
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and so butterfat levels are, in turn, decreased. Alternatively, the changes in the rumen environment in subacute rumenal acidosis could interfere with the biohydrogenation of fatty acids, and milk fat could be reduced in this way.
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* Reduced milk yield (albeit this may not be recognised
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The incidence of a number of diseases is increased by concurrent subacute rumenal acidosis.
on farms where the problem is continuously present);
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* Reduced milk butterfat. There is some debate on the
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precise aetiology of reduced milk butterfat. Traditionally,
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butterfat yield was thought to be dependent on acetate
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production from dietary neutral detergent fibre (NDF),
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although recent work suggests that interference with ruminal
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biohydrogenation of fatty acids may be the underlying
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mechanism behind reduced milk fat (Bauman and Griinari
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2001). However, since rumen pH is dependent on the
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amount of long fibre (physically effective NDF or peNDF)
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in the diet, and milk fat is dependent on the amount of
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NDF in the diet, it is possible to have a situation where
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butterfat levels are acceptable in the face of a ruminal acidosis
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if the fibre being fed is too short to be effective;
   
* Increased numbers of cases of digestive disease,
 
* Increased numbers of cases of digestive disease,
 
including displacement of the abomasum;
 
including displacement of the abomasum;
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