Our White Leghorns stop acting spastic as they mature, but the hatchery Brown Leghorns have not. My husband plans on breeding his accidental WL rooster, Foghorn, he got in our order of pullets this summer to his WL hens. They are his favorite, so it was kind of a happy accident he got a rooster. Having the White Leghorns in with docile breeds like the Ameraucana hen and some Sussex hens have helped to calm them down I believe. They have learned to not fear us because the other birds do not fear us. Hopefully your Leghorns calm down a little as they mature.