My instructions are to feed Gyre normally, encourage water consumption, and see if I can observe him eliminating any urine. If he cannot eliminate, starts really straining, or starts to cry, I'm to page the on-call vet.
So, once Gyre recovers from his knock-out drugs, my evening is going to be spent in the barn with my knitting...
ETA: Gyre is now eating, and produced another weak stream at 6:40 PM. These are good things, both.
At 9PM we visited him again, and again Gyre produced a weak stream to reward us for our visit. He's still uncomfortable, and still doing his little slow potty wiggle-stance.