My five month old puppy used the be the most obedient and faithful dog imaginable, and now its as if he's forgotten all of his training and has better things to do than listen to us!
He's becoming aggressive when we put him into his crate (he hits the bars so hard that the crate will have slid four or five feet by the time we have come home).
He pulls exponentially hard on his lead when we walk him, if he's let off of his leash he walks at his own pace, stops when he wants, chases what he wants, and goes where he wants.
I'm not sure if its where he's finally "dropped" his testicles, or what it is, but its like my fianceè and I are struggling for alpha position with the dog.
Most of the problems were having with him include making him do basic commands which he used to do on the drop of a hat. Things like Sit, Stay, Shake, Come, etc.
I think he's becoming very territorial too, because when our elder male dog comes into the room the puppy will snarl and bark at him until he either lays down next to me or leaves the room.
This is becoming much too frustrating, and we'd rather not see him fixed RIGHT NOW, because we wanted to get a litter out of him prior to his neutering, but at this rate it looks like we're going to have to do it much sooner than expected and loose out on this opportunity.


Is his sexual maturity the reason he's becoming so aggressive? I've never seen a dog do this before, male or female, when they've reached this stage. Whats going on with my puppy?
What are the cures for this problem, (including having him fixed, or aside from)?