I came home to 2 dead chickens this afternoon. They are 5 weeks old. One of the chicks is very lethargic. She is still alive but keeps opening her mouth and doesn't appear to be taking in any liquids. It was pretty warm today and there is 24 chickens in the pen so is it possible she got overheated? I went to the store and got Poly-vi-Sol and mixed it in their water. I mixed some sugar water and a small bit of Poly-Vi-Sol and gave it to the weak chicken via syringe but it appeared to just create a water pocket in her throat. She is opening her mouth like she is gasping so i held her with her head down and gently pushed on the water to get her to throw it back up. It worked but I am concerned that i may have a bigger issue on my hands and i will begin loosing chickens. Any advise?