I have Orps who have very deep keels. My babies have a many forked branch in their large brooder in my greenhouse. At one week of age, they are all roosting up on that forked branch. I have never had a crooked keel. Walt is dead right. I think it is hereditary too.it could be, but I think crooked keels are a genetic defect and roosts are a good thing to blame when you sell defective birds. I have baby's roosting on all kinds of things and I don't remember a crooked keel here for over 20 years.
w.
That roost does serve a purpose in developing strong pec muscles, at a very young age, before the chicks get too heavy to fly well.