I don't like the thought of any animal wondering around suffering in pain, but he deserved it for trespassing and killing your roo. I can relate to this situation. On Christmas day I woke up to my dog barking non stop and I found my huge, mean, but gorgeous goose ripped open. Strange as it seemed, there was a small really friendly Beagle wondering around my backyard trying to get out. Well I found his owners and confronted them about their little killer, but he didn't do it because there was a gigantic hole with gigantic footprints right under the fence. If that little dog dug that whole he would have been so muddy. I scoured the neighbor hood, but found nothing so I put up an electric fence and have not had a single problem since. These dogs took Christmas goose too seriously. I really think the owners had more dogs that dug the hole and this little guy followed them, but I didn't pursue anything.
Good job for getting the revenge that I never got!