Histopathological and immunohistochemical study to determine the effects of monosodium glutamate on skeletal muscle development in chickens

Abstract

The aim of this report was to investigate the effects of MSG administration on embryonic skeletal muscle development in chickens, using histological, histopathological, and immunohistochemical methods. A total of 410 fertilized chicken eggs were used and were divided into five groups: negative control, vehicle control, low-dose group (0.12 mg/g egg MSG), medium-dose group (0.6 mg/g egg MSG), and high-dose group (1.2 mg/g egg MSG). At incubation days 15, 18, and 21, eggs from each group were opened and six live embryos were obtained. The embryos were sacrificed by decapitation, and skeletal muscle tissue samples (musculus fibularis longus and musculus sternocoracoideus pectoralis) were obtained. Sections were stained with hematoxylin-eosin. Moreover, caspase-3 reactivity was determined using the immunohistochemical method. As a result, muscle development was delayed in the MSG groups and the number of caspase-3-positive cells was higher (p < 0.05) than in the controls. Histopathological examinations revealed degenerative and necrotic changes in the skeletal muscle. Muscle degeneration (edema, muscle fiber degeneration, Zenker’s necrosis, and mononuclear cell infiltrations) were observed in all groups, except for the control groups. It was concluded that MSG may have adversely affected the development of the skeletal muscle.