I have 4 new Wyandotte pullets that are 4 months old. I noticed a trace of blood in one of their stools last week. I purchased Corid to treat their water for 7 days. However, I no longer see any blood and everything looks normal with their stool. My question is, do I go ahead and treat all of them, and if I do, should I not keep the eggs of the older Barred Rocks that lay each day? The Wyandotte's are not laying yet.