My dog in the avatar was aggressive towards Other dogs after being attacked by a big black lab on a walk roun our local estate, it just flew out of the house and pounced on him when he was on the lead. From this point he wanted to fight with every dog he seen for months, especially big black dogs! I eventually got him over it an got him to stop te aggression through regularly taking him down the beach and letting him socialise with all the non violent house dogs that are taken down there,spaniels, poodles, pointers etc
To re build his trust in other dogs. He doesn't bother at all with any dog