[Jacob-list] Polio in sheep

[Jacobflock at aol.com]

Pam, the ovine polio is a metabolic disorder and as Neal correctly points 
out, it is a thiamine deficiency which can be treated with B1 if caught very 
early.  Part two asked about heritability.  I am not a vet or a geneticist 
but  this is what I think is going on.

Thiamine depletion (a thiminase enzyme won't release thiamin.. it remains 
bound) might be caused by acidosis, too rich a grain.  This 'rich grain' 
upsets the rumen...  a switch from lousy pasture to 'green lush alfalfa can 
do it....  too much salt and mineral and no water can do it....  high sulfate 
or sulphur intake and low fiber....  A sheep should produce enough thiamine 
to keep its level of appetite in balance.  We can upset that balance in the 
rumen very easily.  

It is possible (but not highly probable) that a thiaminase enzyme gene is 
improperly programed to bind the thiamin and not release it appropriately to 
give the rumen the right pH ... but I would look first to environment issues 
like diet.  If this ram has had any sibs or half sibs that have exhibited the 
same symptoms and had a similar necropsy, then begin to look for a genetic 
cause. 

If the vet did a necropsy and opened the stomach cavity, she should have had 
a strong smell of "rotten eggs" like the hydrogen sulfide generator in 
chemistry.  This just got me to thinking about another evidence question... 
was this ram barned or in an enclosed area with other sheep eating "high on 
the hog" (sort of crowded in) for any length of time with little floor level 
air circulation?  

Fred Horak