Dog is becoming aggressive...help

[Cole]

I've had Jack almost a year (I rescued him the end of November last year), he is about 2 1/2 years old now.

He was a great dog and still is, but now I'm having some aggression issues.

Most of the time the aggression is when another dog comes near me..like a possessive or jealousy type thing. If he is outside with the dogs they will play and play until they drop from exhaustion, but as soon as another dog walks up to me, he become aggressive...growling, showing teeth, and doing the aggressive bark (one loud, high pitched, I mean business bark) and will get in between me and the other dog. I've tried disciplining him and petting the other dog and ignoring him trying to shove his way in between, but nothing is working.

He has also started to become aggressive towards the puppy that lives here. The puppy has been here since May, and is about 6 months old (she is a rescue as well), and is also now bigger than Jack. Jack and Maggie (the puppy) get along great most of the time. However first thing in the morning and first thing after work when we let them out, Maggie will go up to Jack nearly on her belly, with her head down and try to lick his snout (like showing he's the alpha dog). Jack will initially growl and show teeth and if Maggie continues he will snap. If Maggie still continues he will bite her snout, but not hard...it has just enough pressure to make her stop (no marks have ever been found). This continues until Maggie decides to leave Jack alone and go do her business in the yard.

Maggie and Jack play and get along great any other time. They play and wrestle and chase each other and play tug...

I've taken Jack to obedience class and he did really well until near the end. Toward the end of the class he would start growling when the other dogs were close to me but ignored them any other time.

I'm at my wits end. I dont know how to fix this problem.

Jack was a great dog (still is other than this) with a wonderful personality.

But then the aggression started.

I dont know what to do, and would appreciate ANY help or ideas that anyone might have.

I dont like worrying about if Jack is going to attack a dog or a person...I want to be able to trust him.

Thanks.

[NewfieGrl]

A suggestion would be to talk to a few professional trainers, see who you like and get him into a class, or private lessons, immediately. If he's that aggressive you may need to start privately and then move into a class where he can be around other dogs and can be "put to the test". A good instructor will evaluate him and see where he needs to be.
Best of luck.
Michele
Owned by 2 Newfies, a cocker spaniel and 3 cats.

[zig zag zoey]

first of all jack is being posessev of YOU and when the puppy comes up to him on her tummy and likes his snout thats SUBMISHEN the licking is to try to git hin to puck (to take the pup in as his) thats fine if he snapps and that as long as he draws no blud what breed is jack???? git him a chock collor if he doesnt allredy have 1 hock his leash on it and when he pearcks his ears up quckly pull then let go (put the coller right behind his ears and right if you feel under his head you will fel his throt is soft then gits harder put it were its soft and apply presher right when his ears perck up dogs can be the sweetest thing then 3 sechends later bite a finger off thats why you need to carect the ears right when it happens) i will git ree to give you more info