Since my mater plants have started cranking out the goodies, my chickens have been flush with tomatoes. I give them the unsalvageable ones, the end pieces, and the ones I've, ashamedly, allowed to sit on the countertop too long. The littles in the brooder get most of the end cuts. How many is too many? They're eating, at least, a tomato's worth a day. I have 9 in the brooder. The outside chickens eat what they want and leave the rest to return to the Earth, but the littles are absolutely addicted. This has been going on for about two weeks with no apparent ill effects, but I'm a worry wart. They're still eating plenty of starter ration.