Just did a bit of a search on the net for some theories and I reckon some dude has got the best one so far. He reckons its an English Bull Terrier, and because they are a c*nt of a dog to train and can be downright dangerous, people with disobedient or uncontrollable bullies will find them virtually impossible to pass off onto someone else. Then if you cant afford a vet bill to put it down, and your mate Ugene lost his gat in his last 7-Eleven raid, you can imagine somone tieing its front legs together and tossing it over a bridge.