Drugs and pesticide residues in broiler feed can compromise the therapeutic and production benefits of antibiotic (ANT) application and affect gene expression. In this study, we analyzed the expression of 13 key pancreatic genes and blood physiology parameters after administering one maximum residue limit of herbicide glyphosate (GLY), two ANTs, and one anticoccidial drug (AD). A total of 260 Ross 308 broilers aged 1-40 d were divided into the following four groups of 65 birds each: control group, which was fed the main diet (MD), and three experimental groups, which were fed MD supplemented with GLY, GLY+ANTs (enrofloxacin and colistin methanesulfonate), and GLY+AD (ammonium maduramicin), respectively. The results showed that the addition of GLY, GLY+ANTs, and GLY+AD caused significant changes in the expression of several genes of physiological and economic importance. In particular, genes related to inflammation and apoptosis (interleukin 6 (