How are your chicks?
YES! I would absolutely give the outbreak dose if you are seeing blood.
The chicks that are the weakest and need extra care likely will not be drinking very well either, so I would direct dose them with liquid Corid at 0.10 per pound of weight for 3 days (straight liquid Corid given orally).
The direct oral dosage is
IN ADDITION to them drinking the Mixed Corid Water (2tsp Corid to 1 Gallon of water). They need to be encouraged to drink throughout the day. I would give the Corid water for 7 days.
Now. Tell me a little more about how you normally raise chicks. You've been at this for 15yrs. Do you usually hatch your own under a broody?
Coccidia is found in poop and soil - there are 9 strains. When chicks are exposed to Coccidia in their environment, they start to build resistance. Only if there is an overload do you see symptoms - wet bedding, poop gets in the water and they drink it, chicks eat poop (we all know they do!), etc. are some ways that they can become overloaded. Warm brooders also allow Coccidia to flourish as well too. If the chicks came from a different source than you normally use, they may have a different strain or they encountered a strain on your property that they have not yet had time to build resistance to.
Hopefully the Corid will take care of it and they will recover quickly.
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