For example, in infected animals, proteins involved in immune responses such as CCL2, CXCL9, CXCL1, TNFRSF11B, LGMN and CCL5 increased after infection, peaking around day 4 p.i. Additionally, a noticeable yet minor increase in CCL2 levels was observed in the control group in the first 5–6 days p.i. (Fig. 1b, c). Here, CCL2 is linked to infection.