Boy these are good close ups. Where did you ever get them? I think they are a coyote with mange, but I didn't know mange got this bad.
I think too the whole chupacabra thing must be mangey coyote's.
The mange photo came from a Nebraska hunting forum
http://www.bjacked.net/LuvToHunt/hunt/
http://www.book-of-thoth.com/article900.html