Chronic Diarrhea

["Snodgrass, Bonnie" <snodgrab@ncr.disa.mil>]

A good friend has a horse with a nasty health problem. He has a case of
chronic diarrhea. Two years ago he contracted Lyme disease and was put on
Doxycycline from Dec-Feb. The Lyme's was cured and the horse never had any
diarreah at that time. He is a large Han/TB cross that is typically out in a
1-2 acre paddock during at least half the day, which will have some grass
growing in it till fall weather comes around. Anyway, the following fall he
was put into a paddock with another horse who had on again, off again
diarrhea, owner never did anything about it. Peter began to have diarrhea.
Vet was called, took stool samples from both horses and said cause was
Salmonella. Peter was put on ABC's Pro-Bi, other horse was put on a
different brand of probiotic. Other horse cleared up eventually but Peter
never got over the diarrhea completely although he was greatly improved. In
the spring all diarrhea cleared up. The next fall (last fall) the diarrhea
came back with a vengence. The paddocks had been changed by the way and no
other horses in any of the paddocks came down with the symptoms. Vet out
again. Peter put back on Pro-Bi and a form of mettamucil for horses. Again,
some improvement but still some diarrehea with each bowel movement. Peter
has all the good grass hay he wants to eat plus eats the standard complete
feed pellet that the other 40 horses on the farm eats. He was on ABC Plus
vit supplement last year but owner took him off that at suggestion of vet
who wants to keep diet restricted to known elements att. 

When he has access to seasonal grass, he improves till grass growth stops.
Due to the fact that he is a horrible fence crasher (17 hands of dumb-blood)
he is restricted to smaller paddocks that have hot wire on top of wood
fence, so the grass really is limited. His hay is grown on the same farm.
The paddocks were checked for poisonous plants. Never occured until horse
had undergone the antibiotics and or was put into paddock with another horse
with similar symptoms.

Any ideas? Anyone with similar experience?

Bonnie Snodgrass