Quantification of immunohistochemically labelled T lymphocytes and macrophages in the placenta. Box-plot graphs representing the median number of cells, the lower and upper quartiles (boxes) and minimum and maximum values (whiskers) of CD3+, CD163+, CD8+ and CD4+ (see legends) cell populations in placentas after intravenous infection of ewes with 106 Nc-Spain7 N. caninum tachyzoites at day 40 (G1), 90 (G2) and 120 (G3) of gestation. Uninfected control groups (G4 + G5) are also represented. Different letters (a to d) above each column indicate significant differences among groups (P < 0.01). (***) indicates P < 0.001 significant differences between groups.