Lethargic and no appetite

[Engelvis]

Last night we found one of our chickens lying on the ground. She is very weak and there seems to be moisture in her lungs (from what I can hear). We have separated her from the rest of the flock and she has been drinking water, but I haven't seen her eat. I've been trying to hand feed her but she seems to weak to peck at the food.
Her poop seems to be very runny. Any tips on the type of illness and how I can help her recover? She was completely normal until yesterday.

 

[Engelvis]

Last night we found one of our chickens lying on the ground. She is very weak and there seems to be moisture in her lungs (from what I can hear). We have separated her from the rest of the flock and she has been drinking water, but I haven't seen her eat. I've been trying to hand feed her but she seems to weak to peck at the food.
Her poop seems to be very runny. Any tips on the type of illness and how I can help her recover? She was completely normal until yesterday.

Additional info: she is about 5 months old and lives with a flock of 14. Two of the chickens have bumblefoot which are being treated, but none have been recently ill.

 

[Debbie292d]

She is very weak and there seems to be moisture in her lungs (from what I can hear).

Hi,

Do you have any antibiotics?

It may be a severe URI (upper respiratory infection).

I would give them all vitamin water every other day, something like Poultry Cell or Nutri-Drench.

If you don't have any antibiotics, several are available online. Here's one:
https://hardypaw.com/products/fix-mox-amoxicillin-capsules-fish-antibiotics?variant=44787640008865

Amoxicillin dosage is 57 mg per pound of body weight every 12 hours for 7 days.