The last pictures I posted are of a different chick. The fuzzy chick is all black with no other coloration. I have three black chicks of varying unknown linneage. One all black, one looks like a penguin, one has red coming in. None are purebred anything, but hatchery mixes.
Correct me if I'm wrong, but feather sexing on intentional crosses is done as soon as they hatch and refers to the primary pin feathers on their wings at hatch. They quickly grow out enough on cockerels that you can't tell the difference a few days later. I have heard/read/watched people sex chicks based on feather development between 1-2 weeks, as the cockerels are last to get their tail feathers, middle primary coverts, and secondaries. 5 of my 6 have had all these feathers for nearly a week now. The last one is so far behind them. Afterall, Wyandottes are "slow feathering" and all three of mine have more feathers than the mystery mutts, so I'm not sure the feather sexing method applies here.
If the fuzzy one is a sex link like the other two, is she failing to thrive? Should I be worried? They were all the same size and age when I got them. Here's a current picture of the bunch. The one in question is the closest to the camera at the bottom. Penguin to the left and Red on the right. 3 in middle are SLW.
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