Hi there.
Sexing quail can be done in 4 different ways.
1. Observational Sexing: By carefully observing your quail you'd be able to ascertain which are male. Matured quail will be the ones who mount other quail. Do take note that matured males will mount either sex. Females are mounted for copulation and other males will be mounted to establish the pecking order. Cockerels also crow whereas hens will cluck.
2. Feather Sexing: Depending on the mutation of quail you have, it's possible to assess gender based on the matured plumage of your birds. Hens will have spotted or striated chest (or breast) feathers and males will lack these spots. However, certain mutations such as the Texas A&M and Tuxedo quail don't have this trait. Making it virtually impossible to "feather sex" those birds.
3. Vent Sexing: By probing the cloaca (anus) of the quail you'd be able to determine gender. Simply turn a quail upside down, or raise it above eye level, and gently squeeze the cloaca. Matured males will have an engorged cloaca that secretes white foam (this is not sperm). Females are also capable of secreting a tiny amount of foam, but a engorged cloaca is basically never found, unless there is an egg on the verge of being laid. As such, you need to be very gentle when "vent sexing" your quail as a internally ruptured/broken egg will most certainly result in the death of your hen.
4. DNA Sexing: This is the way to go if your quail mutation is sexually monomorphic (no visibly plumage markers). Using PCR (Polymerase Chain Reaction), the presence of male or female chromosomes can be detected. For a viable DNA test you can use vascular material left behind on the inner surface of the eggs membrane, blood or a feather that has the follicle attached. Molt and blood feathers also have no viability for testing.
ABOT