Fig. 1. Haem peroxidase activity in the tick midgut epithelium during blood digestion. Midgut sections were stained for 3-3-diaminobenzidine (DAB) oxidation, and observed by differential interference contrast (DIC) microscopy. (A) First day after blood meal (ABM); arrowheads show contact between digest cells (DC) and the basement membrane (BL). Scale bar, 35 µm. (B) Third day ABM; arrowheads show the diminished contact between digest cells and basement membrane. Scale bar, 35 µm. (C) Day 15 ABM. Scale bar, 60 µm. (D) Day 20 ABM. Scale bar, 60 µm. (E) Day 5 ABM, negative control without H₂O₂; arrowheads show detachment of digest cells. Scale bar, 40 µm. BC, basophilic cell.