Relative mRNA expression of the genes (a) Interferon Gamma (IFNG), (b) Interleukin 2 (IL2), (c) Interleukin 4 (IL4), and (d) Interleukin 10 (IL10) in peripheral mononuclear blood cells of newborn calves with contrasting levels of redox balance, as assessed by the oxidant status index (OSi). The “low Osi” group includes the 6 calves with the lowest average OSi values based on weekly measurements. Data were analyzed using mixed models with repeated measures and Tukey’s honestly significant difference test. Results are expressed as estimated means ± SEM of relative quantity (RQ). * p < 0.05, ** p < 0.01, *** p < 0.001.