If he's losing body mass and looking that awful after only a month, take him to a vet, it almost sounds like he's got some sort of parasite.
What are your temps, what's your setup like, do you have adequate hides, are you only offering him a meal once a week and otherwise leaving him alone, have you tried leaving prekilled in overnight... One month really shouldn't be a big deal to a ball python, I would definately say take him to a vet.
~jenny
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1.1.1 normal ball pythons (Cindy, Darwin, and Periscope)
0.0.1 california kingsnake (tetris)
1.0 rex rat (Scurvy)
0.1 bunny (Spazz)
1.1 betta fishes (Vicious and Killer)
2.2 great danes (Shasta, Odysseus, Merlot, and Watson)
1.0 fat fuzzy mutt (Smokey)
1.1 cats (Thidwick and Turtle)
2.0 horses (Buddy and Sam)
1.0 goat (Billy Jack)
1.25 chickens (Ugly the rooster and his harem)
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