4 year old shih tzu attacking 5 month old newfoundland?

I have a small dog she is a mixed dog she weighs about 8lbs and a newfie he now weighs 120lbs. I had the small dog first they fought at first she was the dominate dog although the size difference. I let them mingale together the small dog will not hurt the larger dog. it is better to let them socialize while the newfie is still a pup.newfies are loving dogs.Mine is very genital with the little dog now .

When I was growing up we went through that with our pekingese and our shepherd/collie mix pup. The little dogs tend to get on a power-trip. Likely the newfie will not attack him, he has probably established his roll as the alpha dog. You'll need to seperate them once and a while (feeding etc) until they get used to each other, one of the best ways to sociallize them is walk them together, if your shihtzu is just being territorial and is generally good with other dogs, you may try a dog park. Try checking some websites on sociallizing/introducing a new dog to your family. Good luck!

Well I have a feeling your Shih tzu is doing it outta jealousy. Territorial rights. Haha. When You have lived there for a long time and another dog just moves in chances are one isn't gonna like it.

My suggestions-keep them apart for part of the day and whenever you aren't home, gradually make them spend more time together always supervised. If the little on starts getting vicious, get mad, tell him/her to stop and discipline him/her. He/she will eventually have to get used to a new dog.

Well are you spending more time with the other dog?The dog could be jealous. Try to spent time with both equally.Hope this helps!Good Luck!

you need to introduce them slowly to each other are they the same sex if they are they both need to be neutered/spayed and see what happens the shi tzu is asserting his authority as boss dog he will get used to the puppy