If the dog does have something like EPI, he can be way low on his B vitamins, and I believe there is a correlation between low on B vitamins and aggressive behavior. I could be all wet on that though, and the nutrition and health experts will correct me. Thyroid can also cause aggressiveness.
With a full exam and bloodwork, and no physical cause for his aggressive behavior. I'm sorry, I know you know the dog, but rather than leave him in a shelter situation, maybe the best thing to do is to put the boy down before he seriously injures someone. You are training this dog in obedience and agility and he is being aggressive. Usually even dogs behaving badly (usually from lack of exercise and mental stimulation) will bond with the people that feed and actively train them. That's not normal. If it is not a physical problem, then there are a lot of normal dogs out there being put down because there is no room for them, dogs that have a hope of finding a real family, and being adopted.
I'm sorry, I know it is hard.
Edited by Selzer (05/08/14 01:47 PM)
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