Re: Short strided sole bruising & Abscesses/PQ question??
IMO, I would put him back on the emergency diet (soaked hay) for a few days, at least. This is almost exactly what my mare did last fall, almost to the day. She was going along well, then completely crashed at a show when she ate the grass under her shavings (which would be the treats for Jasper). This was third week of August last year. She was a known IR but not yet diagnosed PPID at that point. After the show I immed switched to soaked hay and she felt better, but every time I tried taking her off the soaked hay (unsoaked hay <7% ESC/starch; ODTB cubes, etc) she got ouchy and depressed and her insulin soared. Ultimately, the only thing that helped was starting her on pergolide. So in your case, Im thinking you may not be on a high enough pergolide and Jasper's IR is still very sensitive to sugars (I dont think its councidence he took a major dive when you switched from soaked hay of 8% ESC/starch to the ODTB cubes, which would almost certainly be higher in S/S (although still low enough for most, *stable* IRs).
I realize Jasper has other comfounding factors (Lyme, etc) that make his case unique, but as an outsider looking in to his history, the switch from soaked hay to close to 20lbs/day of ODTB is IMO, a huge jump in S/S for Jasper, from what he was on (strictly soaked hay). You also have the seasonal rise adding problems now too. I realize youre concerned about lack of balancing and/or weight loss by going back to soaked hay, but I think you need to get him out of this current crisis first and then go back to addressing weight loss (though one member mentioned his current condition looked good? I could not find a current body shot...but im on my phone which is persnickety in its Neo navigation)
Again, Im no expert, but I was in a similar situation exactly a year ago and wanted to offer the insight I gained from that experience. If nothing else, I wanted to offer moral support for your ongoing, seemingly relentless struggles.
Kerry in NY