Fig. 6.
Effect of weaning age on mast cell (MC) numbers and activation. Porcine jejunum from early-weaned (A and C) and late-weaned (B and D) pigs were fixed in Carnoy's fixative, sectioned, and stained with toluidine blue to visualize MCs. Arrows indicate toluidine blue-positive MCs. Increased numbers of degranulated MCs were observed in tissues from early-weaned pigs (C; ×100 magnification) compared with jejunum from late-weaned pigs (D). E: MC counts were performed in sections from 4 pigs and are expressed as the number of toluidine blue-positive cells/mm2 tissue. a,b,cSignificantly different (P < 0.05) by ANOVA.