I have a young (hatched last year) blue Orpington rooster who has a respiratory infection. I found him under the coop after dark when I checked on them, so I brought him inside and he has been laying down. I can hear him breathing and it sounds congested. He will drink water for me and stands when he drinks. He won't eat though and this has been going on for two days now. Is there any medication that I can give him since he will drink? Maybe something via syringe? He's a big boy, at least eight pounds or more.