I just got a new female Aussie Shepherd and brought her home to my 9 year male Aussie. He is the smartest best most obedient dog I have ever had. He plays with neighbor dogs, we have cats and horses. My one neighbor leave her male Aussie with me when she leaves for up to a week and my dog shares his toys and me. I brought this 10 week old female puppy home and he immediately jumps on it and bites her head. She had a big knot on her head for days. Then I had a hold of his collar and we were trying to get to know each other and she came up to him as if to say hi and he turned his head so fast with me still holding his collar and snaped her nose and broke the skin with a smaller cut that did not require stiches. I then resorted to a muzzle. He attacked her one day in the garage and was on top of her but could not bite her. Last Saturday, she was with my daughter and husband and peed on the floor so they threw her out, forgetting where the older dog was. Luckily they heard her screaming as he was on top of her and going for her throat! She had to have two stiches and just nicked an artery. What more can I do and will we get through this?

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