I have a young (maybe 2 weeks old) chick that started acting lethargic so I brought it and put in a different brooder with younger, smaller chicks so it wouldn't be trampled by it older or more exuberant brethren and I gave it some kefir (probiotic formula) in case it was a digestive thing or it had eaten a shaving or something and it seemed to improve. I've noticed it eating a little in the past two days but mostly it just sits on its haunches and has a "look" about it that just looks like it is sick. Tonight I gave more kefir for good bacteria and then later I noticed when I picked it up and checked on it that below the crop along the right side of the breast bone was swollen and felt like air. I got a sterile needle and syringe and stuck it and pulled the air off until the skin was flat to the breastbone so it was definitely air, no fluid came out and as soon as I withdrew the needle and set the bird down again it began cheeping and it filled right back up again. Anyone know what this could be? Ruptured air sac or something? Is there any hope for this chick or is it going to just waste away and die? I cannot find any wounds on the bird that would cause outside air to get under the surface of the skin so it has to be inernal and the needle I used was 25gauge so very very small wouldn't have left a hole big enough to cause it fill back up from the outside. I'm lost as to what to do for this chick.