Purebred Angus heifers were used to determine the effect of OmniGen-AF (OG) supplementation on expression of cytokines, chemokines, and associated receptors involved in the inflammatory response in whole blood cells of healthy Angus heifers within the first 28 d of supplementation. Heifers were randomly assigned to control or supplemented daily with 56 g OG group (n = 4/group), and fed a diet including grass hay, alfalfa and ground corn. Heifers were housed in a freestall barn and fed via Calan Broadbent system. Blood was collected via jugular before the study started (0) and on d 3, 5, 10, 14, 21, and 28 of supplementation. The qRT-PCR was performed using the Cow Inflammatory Cytokines and Receptor qPCR array (Qiagen). Data were analyzed using LinReg software to account for efficiency of amplification and normalized by 3 internal control genes (HPRT1, TBP, and YWHAZ). qRT-PR data were log-transformed and the samples with Studentized residuals t > 2 removed. The final data set (82 genes) was subjected to ANOVA analysis with treatment, time, and treatment × time as main effect and animal as random using JMP Genomics of SAS. Significance was deemed with a false discovery rate-adjusted P-values < 0.10. Genes coding for chemokine receptors (CX3CR1, CXCR1), stress response (NAMPT), osteoclastogenesis (TNFRSF11B), and angiogenesis (VEGFA) were affected by treatment x time. Thirteen genes coding for interleukins and interleukin receptors (IL1B, IL9, IL1RN, IL1R1, IL10RB, IL10RA), chemokine ligand and receptors (CCR2, CXCL2, CXCR1, CCL26, CCR1), macrophage function (CSF1), and secondary immune response (BMP2) were downregulated and CCL1 was upregulated by OG supplementation. Of the 23 receptors evaluated, 9 (39%) were influenced by OmniGen supplementation. Overall, the data suggest a transcriptional inhibition of genes related to inflammatory response by OG during the first 28 d of supplementation of healthy Angus heifers.