Prenatal Dynamic of Development of Skeletal Musculature of Broiler and Layer Chickens

Results of examinations of the prenatal dynamic of development of skeletal musculature of chicken have been presented in this paper. Eggs of two types of chicken hybrids were incubated – broiler (Ross 308) and layer (Hy-Line Brown). Samples were taken in determined intervals. For the analyses of samples, light and scanning electron microscopy were used. Morphological characteristics of skeletal musculature (muscle of hind extremity – m. biceps femoris and chest muscle – m. pectoralis profundus) were observed: diameter of muscle cells, morphological characteristics of nucleus and cytoplasm of skeletal muscle cells and forming of bundles of muscle cells. It was established that the diameter of muscle cells was greater in layer chicken and that differences in development of nucleus and cytoplasm between these two chicken hybrids exist. These results are explained with prolonged proliferation of myoblasts and delayed differentiation of muscle cells in broiler chickens, which leads to greater development of skeletal musculature of broilers in the postnatal period. The results of this experiment present a basis for further investigations of dynamics of embryonal development of skeletal musculature of chicken, the defining of characteristics of embryonal development of different types of chicken hybrids, as well as the establishment of influence of embryonal characteristics of organism on the postnatal muscle development of an individual.