very sick cchken

[muffin]

I have a very sick chicken he was just fine and then he got sick. He is just a pet and usually very lively. He has two hens and has been o.k. till now. He is very droopy, wont eat or drink, when you pick him up he wants to go to slep, his top red plum is very warm and I have ben treating him with terrmicine antibotic, pedlite, and trying to feed him his food through a sirenge. When I put the liquid or food in his moth he make a gruggling sound and wants to sleep. any help

 

[Buster]

How is he doing? I am sure someone on here must have some ideas on what else to do.