http://en.wikipedia.org/wiki/Chick_sexing excerpt "Vent sexing, also known simply as venting, involves literally squeezing the feces out of the chick, which opens up the chick's picky vent (called a cloaca) slightly, allowing the chicken sexer to see if the chick has a small "bump", which would indicate that the chick is a male. Some females have very small bumps, but rarely do they have the large bumps male chicks possess."
So I didn't squeeze poop out of it but checked against my EE and it definitely has this "bump" they talk about..