What Fresh Hell Is This

I swear to you all, until about three years ago Tristan was the hardiest, thriftiest horse in the barn. Sigh.

Anyway. Arrived at the barn Friday afternoon, having left work early on account of being sick as a dog and leaking phlegm from nearly every orifice. I resolved to pull his blanket and give him a good grooming, write my board check and head home.

I reached under to curry his stomach and - what?

I discovered a hard swelling on his right side, a few inches up from his midline, maybe 8" long and 5" wide. Irregular edges. No heat that I could tell. Not an edema - it was not soft or pitting. Felt like ropey muscle. No clear cut or abrasion.

Utterly stumped, I asked the barn manager to put her hands on him. She was stumped. We asked one of the barn owners to put hands on him. She was stumped.

My best attempt at a picture - you can just barely see the swelling. This is taken from his left side.

WHAT THE HELL, HORSE.

We put him on the longe line, and he looked fine at the walk but was short at the trot through his right side: like he didn't want to stretch his stride out and involve his stomach muscles on that side.

We tossed ideas back and forth and our absolute best guess was that late on Thursday, Tris had been turned out in the indoor with baby Jovi, the coming yearling that he babysits. They go out in a relatively small drylot together, and the idea was to get them both to stretch their legs and to let Jovi get a little feisty and then let Tristan teach him about appropriate boundaries even when you're excited. Apparently they both had a terrific time, and Tristan demonstrated some very energetic and athletic airs above ground.

So, we thought perhaps he had pulled a stomach muscle doing that, and there was some resultant swelling. He got buted Friday night and Saturday morning, and when I checked on him Saturday night, there was no clear change, so some more bute. I'll head out and check on him this afternoon, and we'll see what we see.

Trip to the barn Saturday night. Picture does not quite adequately convey how hard it was snowing, or how much I looooooove my new 4WD + studded snow tires.

The internet suggests many other things it might be, but the vast majority of those things require the swelling to be an edema, which this most definitely is not. The only other outside possibility is a large abscess from a cut or embedded object of some kind, but wow, that would have to have blown up FAST. It's totally in the wrong place for pigeon fever, and he is acting 100% normally otherwise.

I suppose it works out, timing-wise - I am headed to Maine for most of the rest of the week to arrange wedding stuff, so he was either going to get time off or give trail rides to the working students (which they love and he's good at). He can get a week off. If there's no change or if it gets worse, pony earns himself another vet visit.

So much for putting the saddle back on and starting more intensive work...