Mitochondrial function in turkey skeletal muscle--impact on meat quality

Area of Science:

• Poultry Science
• Animal Physiology
• Meat Science

Background:

• The metabolic characteristics of turkey breast muscles, M. iliotibialis (MIT) and M. pectoralis (MP), are crucial for understanding meat quality.
• Variations in mitochondrial function and metabolic state can influence muscle properties and post-mortem changes.

Purpose of the Study:

• To characterize the physical properties, mitochondrial function, metabolic state, morphology, and meat quality of MIT and MP in two turkey strains (BUT Big 6 and Kelly BBB).
• To investigate the relationship between in vivo metabolism, pyruvate oxidation, and post-mortem meat quality traits.

Main Methods:

• Comparative analysis of MIT and MP from BUT Big 6 and Kelly BBB turkeys.
• Assessment of mitochondrial enzyme activity, respiration rates, glycolytic enzyme activity, and pyruvate dehydrogenase (PDH) activity.
• Histological, histochemical, and biochemical variable analysis.
• Correlation of blood lactate with intramuscular pH.

Main Results:

• M. pectoralis showed declining mitochondrial function and stable glycolytic activity with age.
• M. iliotibialis exhibited higher oxidative capacities, while M. pectoralis had higher glycolytic activity.
• Turkey M. pectoralis demonstrated restricted pyruvate oxidation, with lower PDH activity and a correlation between blood lactate and intramuscular pH.
• No significant differences were observed between turkey strains in histological, histochemical, or biochemical variables.

Conclusions:

• In vivo metabolic conditions can lead to intramuscular acidosis in turkey M. pectoralis.
• Acidosis and impaired pyruvate metabolism are linked to compromised meat quality in turkey breast muscle.