I have a female dog and there is a male dog that has gotten into our back yard on a couple of occassions.

Mating. What you are witnessing is the "tie" stage of breeding, where the male's penis is all swollen up and ejaculating sperm. This is the part of breeding where fertilization usually occurres. They stay this way anywhere from 5 minutes to an hour.

Keeping your dog in the backyard to herself when she is inheat (and since she is being bred to another dog, she obviously is) is a very irresponsible thing to do. I realize that you did not know better, but this is why it is the duty of each and every dog owner to read up on responsible dog ownership.

How long ago was this? If less than 48 hours, you can get a "morning after" shot at the vet's office. If more than that, you can have a spay/abort done. I do not recommend carrying on with this pregnancy since you know little about the male. He may have or carry a serious genetic disorder and the pups could end up affected. He may also given a sexually-transmitted disease to your dog when breeding with her. If he was bigger than your dog, this will only cause more complications: (1) her uterus rupture may rupture during the pregnancy due to the pup's possible size, and (2) even if your dog survives the pregnancy, she'll probably end up needing a C-section.
And, finally, since you obviously know very little about dog breeding, to continue with the pregnancy and raise the puppies will be a bad idea even without all the regular risks. There's just so much you've got to know about responsible breeding and how to responsibly raise puppies. They'll need to be properly socialized, for one thing. This is very important, it'll affect their future. Well-socialized dogs are generally friendly dogs while ill-socialized dogs often have problems with fear-aggression. It's a huge responsibility.

My website is an *introduction* to the world of responsible dog breeding:
cookiemiller.tripod.com
~Tiffany, breeder-in-training

Bear, Princess, Coco, & Sheba answered on 11/1/09. Helpful? / 2