There are several on here who trap, spay or neuter and release feral cats. Hopefully one of them can tell you what to do. If you know of a cat rescue in your area maybe they would trap him or give you the cage/trap to do it yourself so you could take him to the vet. Sounds like the poor guy really needs vet attention as soon as possible - and get him fixed in the process so there won't be any Buddy Jrs running around.

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