Can't you just sell them to someone else or let them grow and eat them? Seems like a terrible waste to kill them just because you only females I hope someone else will post for advice for you. Best of luck!
Uuugh...I dont know if i could kill babies right when they are born! How horrible! Maybe its better when he is older and better for meat birds, at least then they would ahve some chance of a life before the inevitable demise!