William Perkins, who farms with his wife, Joan, and their son at Cheadle Hulme near Manchester, told The Daily Mirror the cuts were done with "surgical precision," probably by an experienced butcher. He said the thieves appeared to have used a dog to round up the sheep.
The attackers came at night, with the sheep, including pregnant ewes, found dead in the morning. Investigators believe the motive was to sell the legs on the black market.
"The people who have done this are inhuman to cut off the legs of an animal while still alive," Perkins said.