Sequential evaluation of cerebral capillary sequestration during acute babesiosis. (A) The timing of biopsy correlated with changes in rectal temperature during infection. Animals infected with T2Bo_vir are in red, and animals infected with T2Bo_att are in blue. The red arrows at days 6 and 8 indicate the first and second biopsy for T2Bo_vir infected animals. The blue arrows at days 7 and 9–10 indicate the first and second biopsy, respectively, for T2Bo_att infected animals. (B) Representative photomicrographs of brain biopsies of either the T2Bo_vir or T2Bo_att infected group. First biopsy (panels 1 and 4) was taken one day following the onset of fever. Second biopsy (panels 2 and 5) was taken 2–3 days following the first biopsy. Panels 3 and 6 represent samples taken within one hour of death. (C) Levels of sequestration observed in brain biopsies. There is a significant difference in sequestration between first and second biopsies (p < 0.0001), as well as first biopsy and necropsy (p < 0.0001) for the T2Bo_vir group. A significant difference between the T2Bo_vir and T2Bo_att groups for second biopsy and necropsy (p < 0.05) was also observed.