hens spitting up water and shaking their heads

[taradrew]

I have been noticing my hens spitting up clear liquid when on their roosts at night. They will shake their heads and clear liquid/water comes out of their beaks. I only notice this at night, It started about 3 weeks ago. I had one hen doing it occasionally and now many of them are doing it. They have just recently been out free ranging again. Their egg production has dropped but I think it's because of molting and a recent dog attack that upset them. Their coop is in an area that is quite damp in the spring time. Could they have worms? HELP! Their litter and coop is clean and they were treated for lice about 4 weeks ago.

 

[seminolewind]

I don't know, I've seen my chickens puke clear fluid after drinking, sometimes they just do it, but usually during the day.