Muscle fibre characteristics of a native pig breed longissimus lumborum muscle

Abstract

The aim of this study was to investigate the histochemical parameters of muscle fibre in a Spanish autochthonous pig breed. Due to its fatty meat and high prolificacy, this pork is revered among local consumers. However, the aforementioned breed has become endangered. A total of 11 native pigs (Black Canary Pig) were evaluated. Longissimus lumborum muscle samples were collected in order to evaluate contractile and metabolic characteristics of the varying fibre types by histochemical staining techniques (nicotinamide adenine dinucleotide tetrazolium reductase [NADH-TR] and myosin adenosine triphosphatase activity [mATPase]). Cross-sectional area, diameter and percentage of the fibres were calculated. The oxidative fibre percentage was elevated (33.63%) which in turn can improve the colour, tenderness and juiciness of the meat, hence the glycolytic fibre percentage being moderate (66.37%). The size of three fibre types was higher than the values provided by other pig breeds. A higher percentage of IIB fibres is a disadvantage because these fibres cannot store a high percentage of intrafibrilar fat which could be linked to myopathic process. In conclusion, this autochthonous pig breed could potentially produce red meat and high quality, dry-cured pork products thanks to its remarkably high percentage of oxidative fibres, which naturally possess a greater capacity to store intramuscular fat.