How to sex quail that aren't breeding?

[shelleyd2008]

Most of my quail have stopped laying/breeding. I am taking some younger ones to an auction tomorrow, but they are mostly whites and tibetans. So how do I sex them if they aren't breeding? I assume the swollen gland by the males' vents wouldn't be swollen if they have stopped?

 

[JJMR794]

Idk Shelley.... Never Went By The Gland Thing.... Just Shape And Structures In Vents And That Stays The Same Year Round. Did Ya Recheck The Monarc Sexing Post---- Seems To Me She Had Some Good Pix There That Showed Shape And Structures.