Myogenesis, muscle growth, and meat quality

The steps from determination of mesenchymal cells to myoblasts, proliferation of myoblasts, fusions of myoblasts into primitive muscle fibers, and maturation to highly differentiated muscle fibers are collectively termed myogenesis. The outcome of myogenesis is the neonatal muscle fiber number, which positively influences subsequent performance traits. Myogenesis is sensitive to environmental treatments such as selection for performance, genotypes, intrauterine growth restriction (IUGR), and twinning. Interventions against IUGR are through maternal nutrition and supplementation with e.g., l-carnitine and l-arginine. Postnatal muscle growth is dependent on muscle fiber type and hypertrophy. Muscle hypertrophy relates to two dynamic processes of muscle protein synthesis and degradation, supported by satellite cell proliferation, and affected by genotype, age, sex, and muscle type as well as nutritional strategies such as compensatory growth. The processes of muscle development and muscle growth are discussed in relation to meat quality traits.