Just when I thought my chicken keeping problems were over an new disease has started in my flock. There are no symptoms up until 24 hours before the bird dies. My flock free range 24 / 7 and roost in the trees in my orchard. They have a huge area to roam.. and so are not living in their own chicken poop like in a coop. They get a small amount of fresh chicken feed a day.. in special chicken feeds to keep it dry and clean.. and its all gone at the end of the day so none spoils. They get everything else free ranging. So this is what is happing... I will notice one bird is not with the flock. I find it on its own and moving very slowly.. like in slow motion. 24 hours later its dead. I looked carefully at the dead birds... they plumb, perfect feather condition, everything normal with eyes etc. I have examined a sick one... I can't find anything wrong except its so lethargic and weak. In the last 24 hours the birds comb will loose its bright red colour. I have been loosing about 2 birds a week like this.... 10 birds so far.. one today. Only once did I find one had sticky poop on its butt.... the others had normal poops. NOTE. its only affecting the young birds.. pullets and cockerels. The adults are fine.. only one adult hen got the sickness and she recovered after the 24 hours. I have only had one other young cockerel recover from it. Any ideas of what it could be?