Putting aside the barn owner's thoughts, what is *your* interpretation of your horse's mood? Is he any different than before the move?
Strangers who met my mare might say she's "depressed" -- she is very placid, very stoic, quietly eats hay, scratches on the same fence post, rests under her tree, naps at 11am, never screams or paws for late meals, etc. She's just an old, content horse that does the same boring things each day.
The one thing she does show emotion about is jumping -- she will literally drag you to a jump she gets so excited. There are days I may not feel like riding one more but i do it for her happiness and weight control. Its what makes her happy.
Is there an activity that your horse enjoys? Grooming, or handwalking? I remember he has hock arthritis, but is he sound enough for walks on a nice trail for short distances? It may be that he just needs more of *you* (something he's familiar with) to help him settle after his move
True depression in veterinary terms means withdrawn from normal routine; hiding or not interacting w owners; decreased interest or appetite for food; lethargic/not wanting to move, etc. In general, a change from the animal's normal behavior.
If there has truly been a big change in your horse's behavior then it warrants figuring out what's bothering him. If not, then your barn owner just needs to get used to an old Cushings horse. No big deal. So start by asking yourself if you observe any differences in your horse before and after the move, remembering that some horses are quite stressed by major changes while others will seemingly eat/sleep anywhere.
Kerry in NY
Pinky Sept 2014
Tofurky Nov 2014