Figure 1.

Mean fluorescence area of Mycobacterium avium subsp. paratuberculosis (MAP) present within monocyte-derived macrophages (MDMs) cultured from naturally infected dairy cattle (subclinical n=8, clinical n=8, and noninfected controls n=8). Peripheral blood mononuclear cells (PBMCs) were cultured 5-6 days to generate MDMs, pre-treated with vitamin D₃ as detailed in methods, then incubated 24 hrs with live MAP at 10:1 MOI (A) ± 25(OH)D₃ or (B) ± 1,25(OH)₂D₃. Live and dead MAP were determined using SYTO 9 and propidium iodide, respectively. Data are presented as the mean ± SE. Intra-status comparison significance levels are *< 0.05, **< 0.01, ***< 0.001. Intra-viability comparisons against the control group are a < 0.01, b < 0.001 and intra-viability comparisons against the clinical group are c < 0.05 and d < 0.001.