I don't know about bread, apple, or orange, but I would guess not. On the other hand, my grandchildren cleaned out the basement of all the spiders to feed as treats for my new chicks. Too cute to watch those tiny chicks chase and catch spiders.
No oranges. Citrus is not good for chickens. If you do feed them anything but starter feed you will also need to give them chick-grit -- not poultry grit, but chick-sized grit, or give them access to dirt.
I started feeding them treats from about 1 wk onwards. Greens, stinkbugs, oats, mealworms. All in moderation. Make sure that the feed comprises about 90% of their food intake.
Why would you want to. As a country we already have our children obese and sickly. Why would you want to mess with the chicks? But one thing I find is when I give a little scratch to the mama, she directs them to the light husk things and the smaller stuff. They seem to have a blast with it.
Thanks be to Heaven there's not a fast food for chickens joint.
You can give some things but why would you want to?
If you want them to be as healthy as possible, keep them on starter/grower exclusively. Don't mess with the nutrition that's the result of decades of intensive research into chicken nutrition.
My birds never get anything other than grower till they free range. I've never lost a bird to health issues. Just coons, possums and dogs.
I hang a piece of greens. Kale or spinach. Chickens ate food, real food, long before science and I'm comfortable with that. Bagged chicken kibble from the store left mine vitamin deficient.
I like to give mine treats because it is darn funny to watch.
The treats that get the most activity are crickets, june bugs, and scrambled eggs
(sick, I know). Not only is the protein good for them in these snacks, but the bugs help them learn to forage on their own when they are older. My hens get time free ranging most every day and my eggs are great!