MICROSTRUCTURE OF LONGISSIMUS LUMBORUM MUSCLE AND MEAT QUALITY OF NATIVE POLISH PIG BREEDS: ZLOTNICKA SPOTTED AND PULAWSKA

In 50 fattening pigs representing two Polish native breeds: 24 Zlotnicka Spotted, 10 Pulawska and 16 F-1 female (Polish Large White x Polish Landrace) x F-1 male (Duroc x Pietrain) crosses microstructure of muscle, carcass and meat quality were studied. Pulawska pigs had the thickest backfat, but the loin eye area was smaller only in comparison to crossbreds. Compared to the Pulawska breed, the meat of Zlotnicka Spotted pigs was darker, which was associated with a greater percentage of type I fibres and a smaller percentage of type IIB fibres. Pulawska pigs distinguished themselves from the other groups under study by the greatest density of fibres per mm(2). Smaller diameter of type IIA and IIB fibres and higher total number of fibres were found in Pulawska breed pigs compared to Zlotnicka Spotted, despite the absence of differences in the loin eye area. Smaller thickness of the fibres favourably affects meat quality, and might be considered an indicator of a delicate structure of meat.