u/Decent-Bee-0000

So my dog generally is very friendly. He goes to daycare. Goes to dog parks, no problem. There’s a dog in our building (a border collie of some kind) that came after him twice quite aggressively. Once was in the apartment dog park (we separated them) and once we were on a walk near our apartment and the dog tried to break free from its owner to get to him.

Now, my dog seems to be aggressive and reactive to ONLY dogs that resemble that dog. Today, we’re playing in the dog park and a dog that looks similar to the one who came after him comes in and my dog LOST ITS MIND. Ran up to him growling, barking, and trying to bite him. He nearly latched once, extremely scary. Is this even possible that my dog now has a “type” he is reactive to? I am frustrated and anxious now that this is going to happen with any pup who slightly resembles his enemy #1.

Picture attached reference for the type of dog he’s reacting to (pic is not my dog, my dog is a Labrador).