A stock image of a hen from Belgium [Bloomberg via Getty Images] Hen cages will be banned as part of a raft of proposals to improve animal welfare standards in England, the government has promised. Pig farrowing cages, used to contain sows during birth and nursing to stop them rolling over onto their young, will also be outlawed. The National Farmers' Union said laws should also require imports to be produced to the same standards to prevent unfair competition for British farmers.