Metabolic profiles of three fiber types of skeletal muscle in guinea pigs and rabbits.

The sections in this article are:


1
Motor Unit Types
1.1
Muscle Fiber Types: Histochemical Profiles and Ultrastructural Correlations

1.2
Motor Unit Types: Physiological Profiles in Experimental Animals

1.3
Motor Units in Human Muscle

1.4
Stability of Motor Unit Types

1.5
Developmental Considerations

1.6
Skeletofusimotor Units




2
Anatomical Considerations
2.1
Anatomy of Muscle Units

2.2
Anatomy of Motor Nuclei

2.3
Motoneuron Anatomy in Relation to Unit Type

2.4
Electrophysiological Properties Intrinsic to Motoneurons

2.5
Organization of Synaptic Input

2.6
Control of Motoneuron Excitability: Interactive Factors




3
Control of Muscular Action: Recruitment and Rate Modulation
3.1
Motor Unit Recruitment

3.2
Precision and Stereotypy in Recruitment Process

3.3
Output Modulation by Rate and Pattern of Motoneuron Firing

3.4
Recruitment or Rate and Pattern Modulation?




4
Summary and Concluding Comments

Motor Units: Anatomy, Physiology, and Functional Organization

Roles for the integrin VLA-4 and its counter receptor VCAM-1 in myogenesis

Muscle fibre type and meat quality.

In farm animals (bovine, ovine, swine, rabbit and poultry), muscle fibre characteristics play a key role in meat quality. The present review summarises the knowledge on muscle fibre characteristics and ontogenesis in these species. Myofibre ontogenesis begins very early during embryonic life, with the appearance of two or three successive waves of myoblasts which constitute the origin of the different types of muscle fibres. In small animals (rodents and poultry), a primary and a secondary generation of fibres arise respectively during the embryonic and foetal stages of development. In the largest species (bovines, sheep, pigs) a third generation arises in the late foetal or early postnatal period. Following these two or three waves of myogenesis, the total number of fibres is fixed. This occurs during foetal life (bovines, ovines, pigs and poultry) or during the first postnatal month in rabbits. Contractile and metabolic differentiation proceed by steps in parallel to myogenesis and are partially linked to each other. In bovines and ovines, the main events occur during foetal life, whereas they occur soon after birth in the pig, poultry and rabbit, but some plasticity remains later in life in all species. This comparative survey shows that the cellular processes of differentiation are comparable between species, while their timing is usually species specific.

/pdf/muscle-fibre-ontogenesis-in-farm-animal-species-36mb3kp1bf.pdf

L. Doerr

Papers

Comparative aspects of muscle fiber types in different species.

Postnatal development of fiber types in normal and dystrophic skeletal muscle of the chick

Biphasic development of muscle fibers in the fetal lamb.

Experimental Prevention of Dark-Cutting Meat

Some observations on the innervation patterns of different fiber types of chick muscle