I had the same experience. Did all the research, calculating, etc. Then stopped by the local feed store (not big box, small town) and fell in live with the last 3 chicks they had. So I was off & running with Brahmas, and they are beautiful. 1 turned out to be a Rooster, so he's moved on. They were already 8 weeks, and too shy to get friendly by then. 2 years in and still skittish. They lay almost daily. Big brown eggs
Then bought 2 Golden laced Wyandottes 3 days old and the dog ate them. Had my cry, and went back for 2 more. They're now the sweetest girls, and raised by hand they're really friendly. They lay eggs every 2-4 days, brown eggs
The 5th hen I bought from another feed store, they had grown hens, 24-30 weeks that hadn't sold as chicks. She's Rhode Island Red x Leghorn -we call her Rosie. They said she was laying age and sure enough, she laid an egg in the box on the way home and hasn't stopped laying since. It took a while for her to integrate with the other 2. They beat her up pretty bad. But she's a tough little gal and now dominates the younger Wyandottes.
So there's just no predicting with Chickens.
Advice is buy them young and handle them. They will be easier to handle when you have to doctor or dust them.
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