Definition of "mangelwurzel"

I have not written to my beloved Amelia for these many weeks past, for what news was there to tell of the sayings and doings at Humdrum Hall, as I have christened it; and what do you care whether the turnip crop is good or bad; whether the fat pig weighed thirteen stone or fourteen; and whether the beasts thrive well upon mangelwurzel?

1847 January – 1848 July, William Makepeace Thackeray, chapter 11, in Vanity Fair […], London: Bradbury and Evans […], published 1848

Wheat and barley, oats and hay,Clover, beans, and mangel-wurzels

1943 November – 1944 February (date written; published 1945 August 17), George Orwell [pseudonym; Eric Arthur Blair], Animal Farm […], London: Secker & Warburg, published May 1962