I have a dozen hens and a rooster. I started noticing brown runny poo a week or two ago. Now it's like all I see. My hens are eating well. No symptoms other than the feces that collects flies. Is it worms? a disease? Everything I read about I think they wouldl stop eating or become lethargic. These hens are acting normal.
brown runny poop
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Can you post photos?
Chicken poo can vary greatly. Cecal poop can be runny and stinky to a bit firmer and stinky depending on what they are eating, weather conditions (consuming more water in warm weather) etc. You will see some "runny" cecal poo about 1 out of every 7-8 poops.
I'm in no way dismissing your concerns, but if you are experiencing warmer weather, the cecal poo can become a bit more watery, because of water consumption and of course more flies as well.