Can chickens catch colds?

[ChickenMomsince2025]

My BO has been sneezing once every a few days and when she shakes her head, clear liquid discharges from her nose. Whenever i hug her she shivers. It's been going on over a month. Now two other chickens are discharging clear liquid from their nose. They discharge more frequently when it's warmer like in my car or inside the house.
The weather has been brutal and it's their first winter. I started giving them supplemental heat when it's single digit at night. I get bad rap for giving them heat, but I can visibly tell they're struggling. BO and RIR got frostbite a few weeks ago. Nothing serious, tiny specks at the very top of their combs. That's when I started using brooder plates on extremely cold nights.
I have 6 and 2 of them are going through molt. Last a few days, all 6 of them are content to stay in the coop most part of the day (no supplemental heat during the day). They came out to the run to eat and drink and then went straight back to the coop. This is not normal for them. Are they all sick? Should I consult a vet?

 

[neo71665]

Yes they can. It's not uncommon for birds to stay in the coop when it's cold. Mine also do it when it hits over 100 degrees.

 

[ChickenMomsince2025]

Yes they can. It's not uncommon for birds to stay in the coop when it's cold. Mine also do it when it hits over 100 degrees.

What about the clear discharge from their nose? Should I be concerned?

 

[chooki]

How old are you birds? When you mentioned about the single digit temperature, are we talking about Celsius or Fahrenheit?

 

[ChickenMomsince2025]

They're 10 months old. Right now it's 3F° outside but inside the coop, it's at 15F° and continues to drop.

 

[Eggcessive]

Chickens get respiratory diseases from a virus, fungus/mold, or bacteria. Environmental allergans can cause irritation. The most common disease is infectious bronchitis, which causes sneezing, congestion, mucus and head shaking for around 3 weeks. It spreads through the whole flock, and may cause wrinkled or thin egg shells. The other common disease is MG (mycoplasma gallisepticum) which causes bubbles or foam in one or both eyes, and mY cause swollen eyelids or face. MG can respond to a few antibiotics, such as Tylosin or Tiagard. Are you seeing any swollen eyelids or bubbles in an eye? Coryza and ILT are more serious respiratory diseases.

 

[ChickenMomsince2025]

Chickens get respiratory diseases from a virus, fungus/mold, or bacteria. Environmental allergans can cause irritation. The most common disease is infectious bronchitis, which causes sneezing, congestion, mucus and head shaking for around 3 weeks. It spreads through the whole flock, and may cause wrinkled or thin egg shells. The other common disease is MG (mycoplasma gallisepticum) which causes bubbles or foam in one or both eyes, and mY cause swollen eyelids or face. MG can respond to a few antibiotics, such as Tylosin or Tiagard. Are you seeing any swollen eyelids or bubbles in an eye? Coryza and ILT are more serious respiratory diseases.

No, their eyes are fine. Attached is from this morning. She is one of two that are having symptoms. I noticed white powdery stuff on her comb. Does that tell anything? What do you suggest I do?
Should I have them tested via lab to diagnose? BO has been doing that over a month. Should I go see a vet? Or just keep them warm and watch them?