My dog was raped by 4 other dogs in my dream, what does it mean?

I realise the title is amusing. But it was a genuinely unpleasant dream, in which my golden retriever was raped by 4 other dogs. Two very large black rottweilers and a pitbull and possibly another rottweiler. I couldn't break it up and it was unpleasant to watch. Can anyone shed some light on it? Thank you.