I froze two frames of brood from a German trapping treatment a few days ago, and usually I'll take it out of the freezer the next day, thaw it just enough to uncap it to check for mites, and then feed it to the chickens. Yesterday I took the brood out of the freezer and forgot about it until this afternoon, so it was fully thawed. A lot of the pupae had turned black. Is that normal? Is it okay for me to feed it to the chickens? I tossed this batch because I wasn't sure, but I'm just curious to know for the future.