Ok, So I have been treating all of my chickens with Tylan shots for two nights, there is a respiratory illness going around. Tonight, I come home and all seem better as far as breathing, but two are on the floor and dragging a leg! the foot is drawn up. Could it be from the shot I gave them last night in their thigh? It was on this side, or is it Merreks? They are about 6-7months old. I'm starting to think having chickens is not for me. I get so attached and it seems everyday brings more challenges! So, what do I do? Will they all just die?