The first pic looks like it has been run through a pixel-sharpening filter, perhaps because it was upscaled from a lower resolution, but that's it. The other two haven't been touched at all.

Trust me, I've been using Photoshop every day professionally for the last 15 years.

Anyway, I've seen dogs that look exactly like that up close... thankfully they were tethered... and believe me when I say, they look every bit as scary, if not more so, in person. You DO NOT want to come face-to-face with one.

Like I said before, I'm a dog lover and owner, but I don't consider these animals to be the same as a domesticated pet. They are very dangerous predators, pure and simple, and are generally bred for a very specific purpose: To intimidate and destroy.

And honestly, IMHO, every one of them needs to be put down in the interest of public safety - Believe it or not, that's actually the most humane thing that can be done for these animals.