Morphological characteristics of breast and thigh muscles of slow- and medium growing strains of chickens

Abstract

Morphological characteristics of skeletal muscles of slow- and medium-growing strains of chickens are very important for meat quality and comparison with fast-growing strains. The aim of this paper was to evaluate morphological parameters of breast and thigh muscles of slow- and mediumgrowing strains in a free-range system. The slow-growing strains used in the experiment were autochthonous breeds Sombor crested and Banat naked neck, and the medium-growing strain was Red-bro. The tissue samples were taken from the thigh muscle and muscles of the breast of 10 chickens of each breed. Samples were stained with hematoxylin - eosin and enzyme succinate - dehydrogenase (SDH). The following morphological parameters were observed: diameter of muscle cells, nucleo-cytoplasmic ratio of muscle cells, volume density of connective tissue within the muscle and the presence of red, white and intermediate muscle cell types. Between strains, the type of muscle or genotype didn’t have significant effects on diameters of muscle cells and nucleo-cytoplasmic ratio in the muscle cells. Results indicated that genotype had significant effect on volume density of the connective tissue in breast muscles. Red muscle cells were, in all strains, significantly more represented in m. biceps femoris than m. pectoralis superficialis. Genotype had significant effect on ratio between connective tissue and muscle cells and no significant effects on other morphological parameters. [Projekat Ministarstva nauke Republike Srbije, br. TR 31033]