3 month old male Coturnix losing feathers

[Nabiki]

The feed looks good, so it's not that. I would guess moulting or stress. Those are both things that can be different from bird to bird. Pics?

 

[OnlySympathy]

I don’t keep quail but it sounds like a combination of stress and time of year. Stress can trigger molting especially when it is the time that quail already start molting. And some birds are just weird. I had a 9 month old chicken start molting in the middle of January last year. That is not normal but normal is just the usual not an always