Invisible Shadowmere and Poorly Textured Horses

[FoxiShandris]

To put it simply: Shadowmere is invisible (except for his ass), and other horses in the game that aren't attached to a fast travel cart are poorly textured.

 

I originally put this thread up in Mod Troubleshooting because I believed the only mod I had that changed horses was affecting it (although when using that mod, every horse except Shadowmere appeared and worked fine), but after removing that mod, the problem hasn't improved.

 

I uninstalled the mod and made a clean save, validated my game files, selected Shadowmere in the console and tried disable-enable and kill-resurrect, and nothing seems to work.