Comparative study of the glucolipid profile and GLUTs gene expression in response to insulin treatment across three chicken breeds

Given selective breeding has resulted in pronounced differences in muscle development and production traits among broilers, layers, and silkies, this study systematically compared breed-specific variations in growth performance, serum biochemical markers, and duodenal glucose transporter (GLUT) expression under basal and insulin-stimulated conditions. Herein, broilers exhibited the fastest growth and greatest muscle accretion, accompanied by higher basal insulin and uric acid, but lower blood glucose, urea, albumin, triglycerides, and low-density lipoprotein cholesterol (LDL-c) compared to layers and silkies. Layers had higher basal blood glucose and distinctive duodenal upregulation of GLUT3, GLUT4, GLUT5, GLUT8, and GLUT9, fitting their high energy demands for egg production. Silkies displayed unique serum protein profiles (increased total protein and globulin) and an intermediate metabolic phenotype. Notably, broilers showed a marked, sustained hypoglycemic response and elevated insulin after exogenous insulin administration, which coincided with rapid, transient upregulation of duodenal GLUT1, GLUT3, GLUT8, GLUT9, and GLUT12. In contrast, layers and silkies showed milder and breed-specific changes in serum biomarkers and GLUT expression, with silkies exhibiting delayed but persistent GLUT9 induction and partial suppression of certain GLUTs after insulin. These findings demonstrate that breed-specific patterns of serum biochemistry and intestinal GLUT regulation are closely aligned with physiological and production adaptations in each breed. In particular, rapid growth in broilers is likely driven by enhanced insulin sensitivity and dynamic GLUT response for efficient glucose uptake, while layers and silkies employ alternative strategies for nutrient absorption and metabolism.