The Belgian Blue (French: 'Blanc-Bleu Belge', Dutch: 'Belgisch Witblauw') is a breed of beef cattle from Belgium.[1] It may also be known as the Race de la Moyenne et Haute Belgique.[2]: 95 Alternative names for this breed include Belgian Blue-White; Belgian White and Blue Pied; Belgian White Blue; Blue; and Blue Belgian.[3] The Belgian Blue's extremely lean, hyper-sculpted, ultra-muscular physique is termed "double-muscling". The double-muscling phenotype is a heritable condition resulting in an increased number of muscle fibers (hyperplasia), instead of the (normal) enlargement of individual muscle fibers (hypertrophy).[4]
This particular trait is shared with another breed of cattle known as Piedmontese. Both of these breeds have an increased ability to convert feed into lean muscle, which causes these particular breeds' meat to have a reduced fat content and reduced tenderness.[5] The Belgian Blue is named after its typically blue-grey mottled hair colour; however, its actual colour can vary from white to black.