Adaptations of muscular biology in response to potential glucocorticoid treatment in broiler chicken

Poultry meat production has been dramatically increased in the last few decades due to increased population rate. Glucocorticoids decrease the growth of poultry and increase fat accumulation in liver and meat. In the coming days, it is important to consider the quality of meat to fulfill the increasing demand of proteins. The morphological and biometric properties of meat are associated with the quality of meat. The present research aimed to study the adaptations of muscular biology in response to potential glucocorticoid treatment in broiler chicken. This experiment was conducted into three groups of broilers (i.e. control group: homemade ration, group A: commercial broiler ration, and group B: a high dose of glucocorticoid at 7 mg/kg) started from day 7 to 28. Meat and blood samples were collected at day 7, 14, 21, and 28. For gross morphology, color and weight of meat were measured. Histomorphology of meat was studied under light microscope by Hematoxylin & Eosin stain. The length and width of meat fibers were measured using calibrated stage micrometer. The blood cholesterol dynamics was measured by spectrophotometer. The color of breast meat was more yellowish and lighter than thigh meat. The weight of meat was negatively affected by glucocorticoid. Glucocorticoid treatment negatively influenced the number of myofibers in breast meat, while positively influenced the thigh meat. Excess dietary glucocorticoid increased the biometry of breast meat and decreased that of thigh meat in broiler. Glucocorticoid non-significantly increased the serum cholesterol level. These findings advance our knowledge about the action of glucocorticoid in the muscular system and provide basis for novel therapies to prevent glucocorticoid-induced muscular atrophy.