The Pedigree rare breed pigs left in Britain today are what remain following the introduction of intensive methods of pig production based mainly on the Landrace breed. Most pork is now produced from these very lean, quick growing breeds kept in intensive indoor conditions. Like all factory produced meat it has lost a lot of its character, quality and taste. The price of the meat has been pushed down and margins are so tight that they lead to cost cutting and welfare concerns.
Many of the older breeds have come close to extinction in their past as they have been dropped from commercial pig production. They are not lean enough, or long enough, large enough on the hams or as fast and efficient at growing. But they are hardier and can happily live free range. They are slower growing and cost a bit more to keep and get to suitable weights. But they do produce a better quality meat.
By eating the produce of rare breeds it encourages more people to keep more of them and therefore you will be helping us to save rare breeds; quote from The Rare Breeds Survival Trust