I hope someone can help. We have 27 laying hens that average 18 eggs per day. Recently, they have started eating very little - they have even slowed down eating any scratch. Also, they have reduced their egg production. Today we only collected 9 eggs. Appearance wise - everyone looks fine. They seem to have developed a "cough" - our weather has been very wet lately. Their eyes are clear. Does anyone have any ideas what might be wrong?