In the past I have had the following combinations of dogs:
One neutered male puppy Aust. shep. and one adult male border collie neutered at 2 - Collie marked entire yard first time home after he was neutered and then attacked the puppy a few days later. I got bit trying to scoop up the puppy. Sent the collie back since we had the puppy first.
Then we got a German shep. mix male puppy and neutered him before he came home. The Aust. shep and German shep. got along fine for 2 years then they started fighting while I was pregnant. Had to find the German shep a new home since he was starting the fights.
Now we still have the Aus. shep and a 5 year old spayed Siberian husky. The female is more aggressive but they have been together since she was 10 weeks old.
One neutered male puppy Aust. shep. and one adult male border collie neutered at 2 - Collie marked entire yard first time home after he was neutered and then attacked the puppy a few days later. I got bit trying to scoop up the puppy. Sent the collie back since we had the puppy first.
Then we got a German shep. mix male puppy and neutered him before he came home. The Aust. shep and German shep. got along fine for 2 years then they started fighting while I was pregnant. Had to find the German shep a new home since he was starting the fights.
Now we still have the Aus. shep and a 5 year old spayed Siberian husky. The female is more aggressive but they have been together since she was 10 weeks old.