Horses didn't properly move with barn

I moved my barn to a new location, but for some reason the horses didn’t follow. The other horses went rogue and wandered off, and this horse is just standing here and is unable to be associated with the barn again. I’ve tried turning both the barns shown off and back on again (the left barn is new, right barn is old barn), moving them again, restarting the game, and nothing seems to help. Honestly I don’t really mind, but I keep getting “unhealthy livestock herd” notifications because of this guy, and don’t seem to be able to kill them either.

Ok.
Don’t know if this is a solution.

1.Do you have enough herders?
2. Could that horse belong to the deactivated barn next to it?
3: how far do the herders have to go for food, fodder and housing ? If they are on the road the whole time, they won’t herd. Build a root cellar, well and temp housing close by. If you use hey, build a warehouse and disallow all other items to be stored.
4. Put at least one gate on every side of every field, this might be a tracing bug, so the horses / herders can choose other paths.
5. When gated areas exceed to more than about 30x30 (?estimate) the farm animals sometimes don’t seem to “understand” that the field is gated and are getting rouge more often. How big are these fields?

Question: why don’t you put a farm on the gated area for horses and plant some clover and hey? With low efficiency (4 farmers or so, so you don’t overflow in hey)

Don’t know if that helps at all.

Hope you have fun.

Eventually, they will die. At least, that is what happens to the abandoned animals in my town.

In this game, we can deconstruct abandoned wagons and the cows simply disappear. I wish there was a similar mechanism to either release or butcher abandoned animals.