Yeah, but not feeding unthreshed grain to on-premises livestock.
From Wickard v. Filburn, 317 US 111 (1942)
Thus the penalty was contingent upon an act which appellee committed not before but after the enactment of the statute, and had he chosen to cut his excess and cure it or feed it as hay, or to reap and feed it with the head and straw together, no penalty would have been demanded. Such manner of consumption is not uncommon. Only when he threshed and thereby made it a part of the bulk of wheat overhanging the market did he become subject to penalty.
Threshed, unthreshed, irrelevant to the concept. He grew it, he fed it to his chickens. They considered the very act of threshing to put it on the market, ignoring the basic fact that it was not actually put on the market.