My 5yo male pug has recently started attacking my 1.5yo female retriever.

Has this ever happened to anyone? If so, how did you deal with it?

My 5yo (neutered) pug has always had resource guarding problems, but we just crated him during meal times and there was never a problem after that.

For about a month he’s been randomly attacking my 1.5yo intact golden retriever. We are a household of 6 dogs, he is the only male, and the rest of my females are also intact. We’ve never had an issue before. He lets my 7 month old GR bite and walk all over him and he’s fine with it.

It can start due to absolutely anything, my girl can just be sitting on the sofa and he’ll go for her. My other 5yo female pug will also join in and jump on the bandwagon. It’s become very unsafe having these two in general population around my dog. My Golden Retriever is a perfect dog, she does nothing wrong, has no behavioural problems and is perfectly trained. She is becoming anxious due to this.

We took him to the vets and the vet found an issue with his back, saying that’s most likely causing him pain. We‘ve done the course of anti inflammatories yet nothing has changed.

Please help!