I didn't want to be too descriptive in the title, so if you're eating, you might want to read this later.
Zee is 21 years old, out of work for the last 5, and purchased by me a month ago. I've been riding him for two months, and have seen a liquid discharge prior to pooping soft, but formed manure, not what I would consider diahrea. Sorry, there's no nice way to explain it! He actually has the runs down the back of his legs and a messy hiney when this happens. The previous owner kept incredible notes, and I see that she has "diahrea" noted since July. He had been on Previcox for his arthritis, and I think she thought that what was causing it. He has been off the Previcox for about 6 weeks. We also switched his feed and supplements a month ago, when I bought him. He had been on Triple Crown Low Startch, and we put him on Purina Senior. He only got handfuls at a time to gradually change him over, so it wasn't a sudden switch that started a problem.
So, even with all the changes, the watery poopie discharge is still happening. It actually leaves a little puddle behind him when he's on the cross ties. Last night, this happened 3 times while I was grooming before he finally passed a load of softish manure. We're all kinda stumped. I've heard allergies, ulcers, too much dirt/sand in his belly (our pastures are very overgrazed), or just not digesting something well enough. I would contributue it to being back in work and changing his diet, but this was happening before I got him. He's been on Probios for a month too, when I put him on new supplements, along with SmartProtect and SmartEnergy (both are vitamin supplements, including Selenium A, E, C, and various Bs).
I'm waiting to hear back from the vet, but has anyone else seen this before? Some may say it's just age, but there has to be something I can do to help him out a little bit. I feel so bad for him. He's girthier on the days when I see more discharge, so he's obviously uncomfortable. He also has good days when I don't see this at all for 2-3 days at a time. Could it be richer hay with more alfalfa in it? With a barn of 40 horses and huge hay deliveries, I'm sure his hay varies slightly from day to day and bale to bale.
I've spent most of my life riding horses. The rest I've just wasted.