Blister on horse's withers

[mrs.t]

I have a 12 yr old gelding that we use for trails and as a packhorse.

Recently after packing for 10 hours (5 hours in, 5 hours out) the horse developed a blister on his withers.

After 4-5 days the blister went down and the skin on top dried up and began to peel off. The skin beneath the blister is pink and healthy and hair has started to grow in spots where it has already peeled away. The hair growing in is NOT white (the horse is sorrel.)

There has been no pus, no foul smell, no drainage, no heat, no blood and no sign of infection. The horse has been given a dose of long-acting penicillin and the peeling skin is cleaned daily with a syringe of warm water. I've also kept it soft with a lanolin-based antibiotic ointment.

There is no swelling around the withers, although he is still a little tender near the blister. He is getting around great, eyes are bright, he's perky and has a good appe***e. All in all he seems fine. He has not been ridden since the blister developed (it has been about 3 wks.) The blister needs to be cleaned because I can tell it's itchy - he rolls on it frequently and is trying to scratch it on the fenceposts. Clearly he is not in ridiculous pain in his withers if he can roll on them, right?

However a few people have told me this is fistulous withers and that he is permanently crippled. I cannot see any indication that this has become fistulous withers except for the location of the blister. Has anyone seen this happen before? I suspect it's just a nasty saddle sore and wanted some input.

PS: He has mutton withers at the best of times and unbeknownst to me, the pack saddle used was not fitted to him before he left for the 10 hour ride.

[Elana55]

Fistula of the withers and Poll evil are one and the same thing caused by the Brucella bacteria. The danger with this bacteria is contact with humans (causes undulent fever) or with cattle (brucellosis). As such, I would contact a veterinarian and have a conversation.

Usually, a fistula will not resolve so quickly and will form drainage tubes along the horses shoulders. The pain can be very obvious. This is "old" information prior to antibiotic treatment. Often a fisulous horse was rendered incompetant by the bacteria and had to be put down as the fisula would not resolve. The same can be said of Poll Evil. Again, the pain was obvious.

Today we have antibiotics to combat such things. I know of a horse who developed poll eveil and was successfully treated and went on to live to age 38!

I would thoroughly clean the saddle blanket or padding you used under the pack saddle on this horse. I would also thorougly clean the equipment. I would use a phenol product (do not let you cats walk in, or be around phenols, dry or wet, as it is unsafe for cats). Pine-sol or PenoPine are such products. I know a lot of people recommend chlorox but chlorox binds to dirt and is rendered ineffective rather quickly. Chorox works well only when the surface it is being used on is already clean.

I would call a veterinaraian and ask him if there is anyway to diagnose Fistula at this late date. He may recommend a course of antibiotic specific to the Brucella bacteria as a precaution. The issue with Brucella bacteria is it can "hide" in the tissue, so this horse may need a long course of antibiotic specific to this bacteria to be certain he is free of it.

You are probably wondering where it came from. It can come from infected cattle or other animals such as buffalo and can incubate in soils for long time spans.

Let me know what your conversation with the vet reveals. Thanks!