need help fast

i have jungle fowl hens that are dieing off one by one and dont know why,first they start to get skinny,fethers ruffle wings hanging down,but they still eat crack corn,slow walking i gave them valbazen,1cc mix with 6cc of water,2cc down the throat,and try a shot of tylan50 hope that will help,still died,its a slow death on each of them,they get it one at a time,so if any could help me with this problem please help dont want to lose any more,try to send a pic of the hen