Rescue Collie with agression

Question
Hi, my girlfriend and I just got a 6yo rescue collie named Ozzy from a shelter in Kent, WA. The dog is fantastic. He's very attentive, has slight separation anxiety, and we are unclear about its history. We were very worried about its prey response with our two cats, and he hasn't had any issues leaving them be. The problem that has happened is that my girlfriend (a full-time vet tech at an animal eye clinic) was checking his muzzle because his nose had what looked like a skin problem he snapped at her without breaking the skin. She was startled, but took it in stride as he is still adjusting from his time in flux at the kennel. He hasn't shown me any signs of aggression, neither has he been aggressive to other dogs or people. He has barked at and chased a few dogs at the dog park but normal play without aggression. Otherwise, Ozzy has shown no signs of temper. He greets everyone that he meets with a happy wag and is exuberant at play.
My girlfriend tried to put him in his kennel today, and he bit her on her hand drawing blood. If we take him back to the kennel there is a good chance that he will be put down, and it would break our hearts to have this happen. Several people have mentioned in our research that the breed is known for nipping and herding instinct, but this wasn't a sudden movement and I think it may have been more of a dominance/control issue. It is doubly worrisome, since our good friend will have a baby soon, and we are worried about the future of this dog and whether or not this a period of adjustment for him to find his place in our home, or a sign of things to come.
My question is this: Is there a way to train him out of his aggression towards her? Is the only way of dealing with this behavior problem by avoidance of having Ozzy and my girlfriend interacting? Thanks for your advice.


Answer
This is hard to say, without a complete evaluation, but it's possible, since he is a herding breed, that he might just have instantly associated her with pain, depending on how his nose felt while she was examining it, and now she has become someone he doesn't wish to interact with if she is being physical with him.  I'd like to see you contact a behavior pro at IAABC to get him evaluated.  I don't think this is herding displacement behavior, I think it may be fear related (which can involve control), and possibly very specific to her.  But, since I'm not there, it's best to get the eval.