Apparently, they took the picture to a local "Wildlife Expert" to identify the creature in the picture. Even after consulting references for native Texas animals they were unable to solve the mystery of the creature's identity...
Could this be the fabled Chupacabra? The crypto-zoological rarity whose name means "Goat Sucker", for its reported fondness for feeding on the blood of livestock?
It's a young coyote with a bad case of mange. Took me about .05 seconds to ID it. If you Google "Chupacabra" you'll get tons of news reports and amature videos that feature images of animals that look very similar to this one. They baffle the experts - but not the dog catcher :)
Coyotes in an urban environment face several challenges not faced by their rural counterparts. This is most likely demodectic mange - which occurs when an animal's immune system is compromised too much to combat the mites that cause the hair loss. In the wild, if an animal is injured or sick to the point that it can't hunt it dies relatively quickly from starvation. There's not time for diseases like demodectic mange to progress to the point where the entire body is affected.
In town, though, the coyote is often able to find enough food (garbage, pet food left out) to linger on longer before eventually dying.
I actually saw a news report several years ago on a "mystery animal" (coyote) spotted and filmed locally. They interviewed someone of authority from the Fort Worth Zoo - who declared that it might be some strange hybrid between a domestic dog and an African Wild Dog.
So much for the Experts. :)