I have two young silkie chicks: one is 6 weeks old the other 10 weeks old. When I received them, one was sneezing, lethargic, and shaking its head. The second one began to do the same, so I put them on Tetracycline. Now, after 10 days on it, one is still sneezing every few minutes, and they both continue to shake their heads. Otherwise, they are very alert and vigorous. But I am concerned that something is still wrong with them. The folks I bought them from say this has never happened and that all their other birds are completely healthy. So I wonder if they are allergic to something in the environment. Not knowing what's up, I worry about merging them with my other two bantams --that they might be contagious and make my other girls ill. So, I'd be grateful for any thoughts or suggestions.