Features of the microstructure of the quadriceps femoral muscle of broiler chickens of the smena-9 cross with various feeding diets

The article presents the results of studies of the histological and ultrastructural characteristics of the quadriceps femoral muscle of broiler chickens of the Smena-9 cross on the 35th day of postembryonic ontogenesis using feed additives (probiotic, prebiotic, sorbent) of domestic production in addition to the basic feeding diet.The work was implemented within the framework of the thematic task plan for the implementation of research works under the state order of the Ministry of Agriculture of the Russian Federation (Agreement No. 082-03-2023-238 dated 30.01.2023) on the topic: "Development of theoretical foundations and methodology for the practical use of morphological criteria in assessing the quality and safety of poultry products." It has been shown that against the background of the use of feed additives, an increase in the weight of chickens occurs. At the same time, the microstructure of the rectus head of the quadriceps femoris of birds of the control and experimental groups, while maintaining the general plan of structure (the presence of muscular and connective tissue components, bundle organization), is not the same. Based on studies using light and transmission electron microscopy, it was shown that the signs of morphological maturity of skeletal muscle tissue are most pronounced when using a probiotic, in the case of using a prebiotic and a sorbent, muscle fibers grow less synchronously, which is manifested by the variability of their thickness. The thickness of muscle fibers, their bundles, the state of the mitochondrial apparatus, the packing density of myofibrils and their thickness, the degree of development of endomysium and perimysium and the presence of white adipose tissue can be objective morphological and morphometric criteria for assessing the condition of muscle tissue, which correlates with the taste qualities of poultry meat. Data on the structural organization of the quadriceps muscle of the new domestic cross expand the theoretical base in the field of the myology of farm birds, including in terms of identifying morphological signs of the realization of genetic potential against the background of the use of different feeding diets in chicken rearing technology, which allows us to quickly assess the effectiveness of chicken rearing technology and predict an increase in productivity.