Mitochondrial energetics and ROS production in chicken skeletal muscle: Application of modular kinetic analysis

Mitochondrial ATP production or heat production can be a major factor in the conversion efficiency of food/feed energy. An inappropriate control of mitochondrial reactive oxygen species (ROS) production will exert a negative effect on development of tissue and organs, and hence animal growth. To elucidate how alterations in mitochondrial functions specify their ATP production and oxidative damage, modular kinetic analysis was applied in 2 typical mitochondrial studies concerning the differences (a) in oxidative phosphorylation between meat- and laying-type chickens, and (b) in ROS production between heat-exposed chickens and its control group. Skeletal muscle mitochondria from meat-type chickens were found to have a higher oxidative phosphorylation efficiency than laying-type chickens. In the heat-stress conditions, 'substrate oxidation' by the electron transport chain was enhanced, reinforcing mitochondrial superoxide production, probably via an elevation in the membrane potential (ΔΨ) in avian muscle mitochondria. Thus this method is of value tool in consideration for improving of growth performance.