Thank you for taking the time to write this. That was very informative! It feels like there are so many aspects that should be studied now chickens are becoming pets, instead of just livestock.Yet one more thing we should know and understand about chickens but don't.
From chick to fully feathered pullets there are either 3 or 4 moults depending on who one consults.
Most chickens undergo a moult of some sort after the summer. Some chickens moult at other times of the year.
Some hens (first full moult usually) have a hard time of it and look dreadful. From what I've seen, as the hen matures the moults become less sever.
Rooster moulting, again from what I've seen can go on throughtout the year and there is no drastic loss of feathers at any point.
The above is a generalization and that's about as good as it gets when it comes to the complexities of how biology functions. We may find that a particular combination of circumstances will trigger a moult but until we know exactly how it all works we won't be able to predict a moult.
I'm not suggesting you have forgotton but chickens are not machines which for some ridululously small percentage error, will do the same thing until it breaks.
In other words, they are predictable. Most creatures behaviour is not easily predicted.
An interesting view from one of my Catalan keepiing friends on why battery hens have such major loss of feathers isn't so much that they get pecked out, more the hen is constantly stressed and undergoes stress moulting. Of course, any feathers that drop out get eaten by the other chickens so even if one wanted to properly investigate this it would be incredibly difficult.
Blanche has always been a stressed hen, that's why I wondered if there could be a correlation.
I've had two friends in the last ten years suffer from complete loss of all hair (head and body) after a huge shock, I know humans physiology is completely different from birds, but I think it's also why I thought of stress related to molt.
Excessive feather loss in a flock (which I'm not comparing to usual molting as I suppose most of it amounts to feather picking) is mentioned in some of the studies that have been cited on this thread as one of the indicators of well-being , or rather unwell-being.
Blanche