How old for vent sexing coturnix?

[brewer12345]

My new batch of quail hit 6 weeks today and I need to start sexing them. There are 37 birds in this lot and they are all running around one pen. The 15 browns were easy to sex (although only 5 were hens). The problem is the A&Ms. There are so many birds in the pen that I have no idea who is crowing when they do it. I can think of two ways to deal with them:

- grab 5 or 10 A&Ms at a time, put them in an auxiliary pen (old guinea pig excursion on the grass pen) and sit there with a book waiting for one to crow (band him on the spot).

- Pull the A&Ms and vent sex them one by one.

I have seen vent sexing done, but never tried it myself. How old do they have to be before you can reliably vent sex them? Any other ideas to deal with this?

I think this is the last time I do A&Ms, since it is so much easier to sex the browns.

 

[Jedwards]

I have read before that if they start to crow you can usually vent sex soon. I have noticed that I don't have luck vent sexing the males until they start breeding ~8weeks. I stopped A&M for the same reason haha good luck!

 

[Duck Drover]

I have Texas A&M quail too and vent sexing is not as easy as I thought it would be but maybe they are not sexually mature yet. I have been doing the the sit and watch for a crow and then band method but with so many popping around it is hard to tell where every crow comes from and no crow does not guarantee hen. Feather sexing other colors is so much easier in comparison!