Hoping to revive this post for a similar situation...
I have 4wk old chicks of various breeds that were hatched and brooded together by a neighbor (plus ONE a few days younger that we managed to hatch

) As a note, a few days ago we turned an old water trough/duck pond into a bigger brooder outside for them. It had been dry and cleaned for months but left in the coop. I filled it with new straw and some old dry hay that had fallen below the bunny hutch, near the quail coop.
Yesterday I noticed red mucousy remnants on one chick, and then saw a bright red dropping. Everyone otherwise appeared happy and healthy. This morning my husband found a different chick dead. And I see more bloody poops! I took pictures of what I saw today. It looks a bit different than OP's but my husband is picking up some CORID right now anyway. Is that the right treatment? And is there anything else I should do?
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