The effect of dietary magnesium oxide supplementation on postmortem 31P NMR spectroscopy parameters, rate of Ca2+ uptake and ATPase activity of M. longissimus dorsi and meat quality of heterozygous and normal on malignant hyperthermia pigs

Abstract Twenty four crossbred (Large White, White Meaty, Pietrain, Hampshire) pigs were tested by DNA probe for a mutation on the ryanodine receptor RYR1 (malignant hyperthermia-MH). An equal number of pigs heterozygote (monomutant-MON) and normal on MH (nonmutant-NON) were used in the experiment. The pigs were fed finisher feed (control group) or finisher feed supplemented with magnesium (3.6 g MgO per pig per day; MgO group) for 5 days prior to slaughter. Pigs fed the diet supplemented with MgO had higher plasma Mg concentrations. Phosphorus nuclear magnetic resonance ( 31 P NMR) measurements on postmortem (15 min) muscle samples ( longissimus muscle) showed the highest phosphocreatine levels in normal pigs fed MgO ( P 2+ uptake and Ca 2+ ATPase activity only in normal (NON) pigs. ATPase activity was lowest ( P P P 2+ uptake and meat quality (pH, drip loss).