Carnosine plays an important role in regulating muscle buffering capacity and glycolysis. In order to investigate the effects of dietary β-alanine,L-histidine and L-carnosine supplementation on the pH value, glycolytic potential, the activities of AMP-activated protein kinase (AMPK) and pyruvate kinase (PK) activities in the porcine longissimus dorsi muscle, a total of 60 barrows with an average body weight (BW) were assigned into five groups which received diets containing basal diet (control,

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... CON), 0.04%β-alanine (β-ALA), 0.06% L-histidine (L-HIS), 0.04%β-alanine+0.06% L-histidine (β-ALA+L-HIS), or 0.1% L-carnosine (L-CAR). The results showed that dietary supplementation of the combination of β-ALA and L-HIS or L-CAR significantly increased (P < 0.05) the average daily gain (ADG) of pigs with 50-75 kg BW, compared with other three groups. Compared with L-CAR group, L-HIS supplementation significantly decreased (P < 0.05) the average daily feed intake (ADFI) of pigs. There were no significant difference (P > 0.05) in back fat thickness and loin eye area among treatments. At 0, 1 and 24 h postmortem (PM) the pH values in the longissimus dorsi muscle (LM) of pigs receiving L-CAR were higher (P < 0.05) than that of pigs receiving CON diet. The redness (a*) values of LM of pigs in the β-ALA+L-HIS or L-CAR group were higher (P < 0.05) than those in other three groups. The glycolytic potential of LM was not significantly different (P > 0.05) among treatments. At 1, 24 h PM the AMPK activities in LM of pigs receiving β-ALA, β-ALA+L-HIS and L-CAR were much lower (P < 0.05) than those of pigs receiving CON diet or L-HIS. 0.1% L-carnosine or 0.04% β-ALA supplemented to pigs diet was effective in regulating AMPK and PK activities in the porcine longissimus dorsi muscle and preventing the development of pale, soft and exudative (PSE) pork.