The Cornish X are new to me, I have never had birds with these troubles before. They are 7ish weeks now,,, one died last week,, culled two yesterday that had runny poo and didn't move for two days,, put the remaining 9 in a tractor with cracked corn hoping to keep away from where the sick ones were,,, today,, one more not moving and I saw piles of what looked like black RTV from another. Any Ideas what it is? What should I do? Cull or process them,,, I don't want to eat a sick bird. I have a mixed flock and the only other 3 losses were two from hawks and one at sunset from an owl. The rest are all healthy.