Abstract: Different driving methods before slaughter cause different levels of stress in pigs, thereby affecting pork quality. In this study, 45 six-month-old pigs were randomly equally assigned to mild driving (MD), sound driving (SD) and traditional driving (TD) groups. Stress-related blood parameters, muscle parameters and physiochemical properties were determined after slaughter, and the regulatory proteins affecting muscle energy metabolism and meat quality were identified by proteomics analysis to explore the potential mechanism for the impact of different preslaughter driving methods on pork quality. The activities of creatine kinase and lactate dehydrogenase in the MD group were decreased (P < 0.05) compared with TD group. The lowest stress level was observed in the MD group. MD could result in significantly higher a* value and pH at 45 min and 3 h postmortem, but significantly lower cooking loss (P < 0.05) as well as reduced incidence of pale, soft, exudative meat compared with TD treatment. Glycogen and ATP contents in the MD group were higher (P < 0.05) than TD group at 45 min and 3 h postmortem. Similarly, stress level in the SD group was lower than that in the TD group, with intermediate levels being observed for creatine kinase activity, lactate dehydrogenase activity, pH at 45 min and 3 h postmortem, and ATP at 45 min and 3 h postmortem. By proteome analysis, 46 proteins that differed among groups were identified including ATP-dependent 6-phosphofructokinase, alpha-1,4-glucan phosphorylase, glycogen debranching enzyme, glyceraldehyde-3-phosphate dehydrogenase, phosphoglycerate kinase 1, isocitrate dehydrogenase 2 and mitochondrial creatine kinase 2 and myosin-7. In conclusion, both MD and SD can reduce the rate of energy metabolism in muscles and change the state of muscle contraction, thereby increasing postmortem pH, glycogen and ATP levels and ultimately improving pork quality.

Key words: mild driving, traditional driving, energy metabolism, muscle contraction, pork quality