Genetically, they should all be able to interbreed, also with wolves and coyotes. However, there are quite a few breeds that are known to have breeding and bir

Genetically, they should all be able to interbreed, also with wolves and coyotes. However, there are quite a few breeds that are known to have breeding and birthing problems. Some unable to properly mount each other and breed. Others with hips too small to properly birth and need close to 100% C-section delivery. I can imagine these problems could be exacerbated by attempts to breed with other larger breeds.