I know their is wing sexing, but I dont know how to do it and I think it only works with some breeds (not sure) and it needs to be done within the first few days. Otherwise you just have to wait a while and watch their combs/wattles.
Yup wing sexing only works with a fast feathering bird and a slow feathering bird. Therefore I doubt you can use it, but you never know.
I heard, but I'm not sure, that you can vent sex by looking at the chick's vent when you open it/it opens and for roos you see a pimple like thing. But it doesn't always work considering roos can have tiny... Tools... While females can be a bit more masculine.
I'd also like to know the answer to this Q. What about their combs and wattles? My chicks are almost 4 wks old and I'd like to be able to separate the pullets from the roos (mostly destined for meat) before I put them out in the tractors. We only had $$ for hardware cloth for the hens, so I had to use chicken wire for the roos. The hens were significantly more expensive, so I don't want any mixups since the rooster run is less secure. I can keep them all in the hen run/tractor for a while, but with 46 of them they'll need to be separated soon for space reasons. Any hints??
I've had pretty good success with sexing by looking at their legs/ankles (compare a couple of chicks from the same hatch date) and also feeling the "heftiness" of the bird in question as a roo, compared to his hatch mates. The roos, right from the start, seem to have larger diameter legs in the ankle area. And ironically, I picked up one that I thought was roo-ish from the legs and I could immediately tell that he was significantly heavier than his hatch mates. Sure enough, they're now 10 weeks old and he has a good red comb and wattles going on...definite roo.
My last batched confirmed to me that females' feathers grow faster. At one week old I was able to tell which would probably* be female and which one male. The female had her flight feathers extending to the end of her body and the male didn't have as much growing.
*I say probably because it might be different for different breeds and it's more of a rule of thumb I think.
Got another batch hatching about now so in about a week I'll be able to see again. I have a mixed breed flock so it'll be interesting to see just how much this'll happen.