My 8.5 month old GSD is pushing his boundaries. Will keepin gmy Border Collier permanently affect my GSD's development?

Hi Cindy,

I have read many articles on your website and also purchased and viewed (and still viewing) your DVDs. I have currently got a 4th dog, which I was supposed to have in joint-ownership, however it seems that I will have it all by myself unless we return him to the rescue center. I am currently following your advise from DVD Establishing Pack Structure and Article Ground work. To Explain, my existing pack (I had all 3 dogs from pups) consists of:

1) 3.5 Year old JRT bitch - spayed - which is the Top Bitch - she is obedient, building her confidence at Agility, barker but otherwise she is well socialized with people, dogs and all different situations.
2) 3 Year old JRT dog - neutered - very mild temperament, not pushy, doing competitive obedience, again very well socialzed with people, dogs, and all different situations.
3) 8.5 month old GSD - pure working line, dog, intact (and do not wish to neuter him) - progressing very well in training - obedient on command for his age, increasing distractions, well socialized with people, different situations and environments, good with other dogs while off lead on walks, playfull - has good drive & focus and we are starting protection training with him...
4) The new rescue dog is 6.5 months old, intact male, border collie - he has lived all his life closed in the house, the former owners did not even had lead and collar for him, under socialized with dogs - but not afraid, does not know how to play, over submissive at the moment, very good with people - progressing lovely in basic comands - in less then 2 weeks we managed recall, fetch, sit and starting down - very eager to please, very mild temperament - will not be pishy dog.

My question is: My 8.5 months old GSD is starting to push where his boundaries are, started to be dominiering / guarding his resources / space - not towards me but other dogs. I know I have to be persistent, consistent and do not let him get away. How would you correct the behavior? One of the trainer push him down when he started to guard agility tunnel and steamed up chaos, then when we were training focus turns - turning to the dog (oposit to heel work) he started to nipp on my legs and sleeve, so the trainer, took him by the collar, hold his head up and said sharply Nooooooo. Then when we walked among 20 other dogs and there was a scruffle, the trainer put his hand into clows and twisted the scruff and again said sharply Nooo ... I am wondering whether this is a good way of correction. I have used your market training so I never really tagged my dogs, screamed at them or was rough. Can you please advise me? I would like my GSD to let any dog into house, garden car without growling, intimidating him just tolerating him as the two JRTs I have.

The last question I have, do you believe that keeping the Border Collier permanently will affect my GSD development? I was told its good to have him temporary for some time and train my GSD to accept dog, but not permanently. My GSD & BC are getting much better together, and if I keep the BC (He is really good natured dog and will excell in Agility as he is very lightly build) I would neuter him.

The key is to learn how correctly I shall correct my GSD when he is traying to be dominant, pushes his boundaries. I was told that my Hey AAaaaaaa would not suffice now as he is maturing. My GSD is now 90 Pound and I was told he will be about 120 pound dog, he is going to be large strong mail when he matures.

I am sorry for long question, and thank you for your input. Please note my GSD is not agrressive dog - but if I mishandle this period of his development / correction I can crate it. Please help!