Hi, So we have a flock of chickens, about 30 leghorns that are one and two years old and 20 isa browns from this last summer. Recently our leghorns have started dying which I thought was because of old age. But this week seven have died and one of the ise browns. The thing is the other chickens ate the feathers off the dead ones which I haven't noticed them doing before. Also they started attacking another Ise Brown. Any ideas as to why this is?