True for nearly anything in the animal kingdom and certainly for everything under class mammalia, so that's definitely not all there is to say.
Yeah, it is. Because you shouldn't kill anything (yeah, yeah, I know killing for food/survival is different) you don't have to. And if you're going to, in the case with these dogs, you should do it humanely. Killing animals in mass quantities is bad enough, but if you can't figure out a quick, and clean way to do it, you shouldn't be doing it at all.
To go back to the point that Gorgon made, he's right. There are people all over the world with horrendous diseases like AIDs, living in conditions worse then some of these dogs. Let's just kill all them too, you know, just to be safe.