My pullets are almost 17 weeks old and still don't cluck. I have BO's and GLW's and none of the pullets cluck. My BO cockerel has been clucking and crowing for several weeks. He puts the girls to shame, but all they do is this kind of purring sound, almost a whine. It's cute but I'd like to hear the flock do a little clucking too. Are they just slow?