Join Date: Nov 2010
Location: Northern Illinois
I would assume its pain honestly.
If he was perfectly okay with it before and it suddenly changed, that's a red flag for pain.
Is he well behaved when you do other things? Can you touch his stomach and other parts of his body fine? If it is an attitude thing, it would show up in other areas (such as training issues, catching, brushing, standing, etc). Are you having any other attitude issues with him?
I would rule out pain before I assumed behavioral. If he is in pain and it hurts to clean it, he is only going to get worse if you do discipline him.
** Don't be the rider who gallops all night and never sees the horse that is beneath him **