Growling at other dogs and at me...

[Gracie's My Girl]

It seems like when you are raising a puppy...you can go from one challenge to the next.

Last week we went back to dog class because we hadn't been in a while and I needed to discuss some boarding arrangements with the trainer. We train underneath a large picnic pavilion that is lighted because it is dark outside. Gracie got the bright idea to growl and snarl at the other dogs. It wasn't something she did the entire time we were there, but if a dog approached her...she would occasionally become defensive. It probably happened three or four times in an hour. My reaction was to tell her "No!" and then move on to something else and not dwell on it.

This new behavior is a mystery to me because she is generally good around other dogs. She likes to keep her distance, but usually friendly. We had her with some other dogs over the weekend and she was fine with them. Is what happened that night just a fluke or something I should be concerned about? How should I react if she does it again?

Just this afternoon, she took an interest in her flavored Nylabone and began to chew it. We've had it for months and she has never given it a second look until today. I let her chew on it for a while until I needed to crate her and clean the house. I reached down to give her a little scratch behind the ears and she growled at me. Once again, this is not something she usually does. I have had it happen once before when she was chewing on a soup bone and it was time to give it up. All I did in response was tell her to leave it and then swapped the Nylabone for a treat before crating her. Gracie was stubborn and it took a couple of tries and she ran away from me until I picked up the leash, but she finally did what she was supposed to do.

I would appreciate any advice on how to handle these situations. She is rarely possessive of her toys or treats, so I have never felt that I needed to train her extensively in this area. What can I do fix this problem? She is seven months old and I would hate to not step in before these issues get the chance to become worse.