The eggs broody Chipie is sitting on, both Chipie and Théo, and the advice on the egg-bread mixture for chicks come from a 75 year old farmer, Gaston.
He doesn't view his animals like I do mine at all. They are livestock and have no name except for the dogs. He does care a lot about them, and this has always been the way he spends his whole days, but he cares for a flock/herd, and he will always give priority to overall vigor over saving one individual. For example he will go through a lot of trouble and time and pull some pretty disgusting tricks of the trade to get a motherless lamb adopted by a ewe, but he doesn't bother to treat a lamb with vitamin deficiency which is very common and easy to treat.
In his way of thinking using a homemade mixture to feed chicks makes sense because time for preparation isn't a criteria and the broody will indeed take over and the chick will learn to forage for itself, whereas using medicated starter definitely wouldn't. I'm not in the same mindset and for my chickens I wouldn't value public health above each individual life

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