As a pet owner, you are responsible for your dog. If he impregnates the dog next door, you may be held responsible for those puppies, just as if your dog were to bite someone, you are responsible. If your dog does impregnate the dog next door, it means your dog hasn't been neutered. This is one of the reasons why he should be. If you aren't sure if your dog should be neutered, read on for a few other reasons why he should be neutered.