Fig. 2. Delay in lobuloalveolar development in Stat6^-/- mice. (A-C) Whole mounts (left panels) and haematoxylin and Eosin (H&E)-stained sections (right panels) of mammary glands at day 5 (A), 10 (B) and 15 (C) of gestation from wild-type (WT) and Stat6^-/- mice. Images shown are representative of at least three mice. (D) The number of alveoli was scored in H&E images from wild-type and Stat6^-/- mice at 40x magnification and the area of the fat pad was measured using ImageJ software. The number of alveoli/mm² was calculated and the percentage relative to wild type was plotted. Student's t-test was performed and ^*, ^** and ^*** indicate statistical significance with P values of P<0.001, P=0.011 and P=0.052, respectively. (E) Proliferation rate was measured by scoring for Ki-67-positive cells from three different fields at 400x magnification. Error bars represent s.d. of three independent mice. Student's t-test was performed and ^*, ^** and ^*** indicate statistical significance with P values of P<0.001, P<0.01 and P<0.003, respectively.