What happens with Cocidiosis is basically this, the protozoa invade the intestinal tract where it causes hemorrhaging, then the chicks cannot absorb fluids; therefore, dehydration sets in, that's per Mississippi State Poultry. They expected my last four out of seven wouldn't make it, .... but they did and they are doing extremely well.
What I first noticed is one chick sitting looking "fat, dumb, and a bit sad". HINT THE CROP LOOKED FULL, and bloody poops, because they couldn't absorb water nor food through their digestive process.
Then the next day, it was doing the same thing, .... then there was a 2nd and 3rd chick out of the ... seven were doing the same too. I knew then what it was .... heavy rains, feed on the ground where they spilt it, and chicken poop etc. I immediately isolated the seven that were incidentally already still in a chicken tractor that was inside our bull paneled chicken runs. I still removed them, shut the access to the chicken tractor, and brought them into what we called their baby beds, lol. The first one died on day three, the second by that evening, then the third the next day. That's when we stepped up our game by giving the Corid mixed water via small syringes by mouth(s), plus ProMoxil mixed with water, and then B Complex with Electrolytes ... also mixed with water. We did this several times a day and a couple times at night. After several days of doing this, we still had one that we expected to die hour by hour. So, we thought, well win, lose or draw ... we had to go the extreme ... two drops of straight Corid, followed by the ProMoxil water and B Complex Electrolytes water. That SAVED that chicks life.
We've only had chickens since late July, so initially we had one rooster (Harold - Rhode Island Red/Fighting Rooster mix) given to us to have for dinner. From that point on we added
TSC chicks, were given two mixed fighting hens, .... gave those two back plus six hens to the teen. Then bought four, Silver Laced ... then the seven, THEN 29 MORE SILVER LACED, and four Brown Hens (for our own eggs). So in ONE YEAR WE ARE AT FOURTY EIGHT CHICKENS! How's that for "chicken math"!
You can't tell they ever missed a meal today, and this all happened last April/May.