I believe dog to dog aggression to be bred for is as simple as breeding dog aggressive dogs together, but that does not mean that all those dogs will fight. (btoellner.typepad.com)
Also as a note, dog aggressive dogs under control and with responsible management have just as much right to be out and about as the friendly neighborhood pal. (thedogsnobs.com)
We try to not take a known biter, we have taken dog aggressive dogs, but they are very hard to place and require a long time in foster care with a behaviorist working with the foster family to help the dog. (grca-nrc.org)