When FDR became president, he took economic desperation as a blank check to do anything to fix the Great Depression. The federal government explicitly had no power over local manufacturing and employment, so they created the power by reinterpreting anything that hypothetically might affect later interstate commerce as if it were interstate commerce. So birthing too many piglets was the same thing as selling too much smoked pork across a state line, and the federal cops would come to your farm and correct it by killing the unlawful piglets.
This should probably have resulted in the rape of Washington, D.C., but at the time Americans were starving in Bangladesh-style tent cities and were willing to put up with a lot. Also local governments were flying the Communist flag and high federal officials were openly espousing Stalinism, so an unconventional jobs program that worked raised few eyebrows.