Fig. 7. (A) Mean tracheal diameters over multiple generations during the first trial. Shaded areas indicate the generations during which all treatment groups were raised in normoxic conditions. (B) Tracheal diameters at the posterior anastomosis over multiple generations during the second trial. Shaded areas indicate the generations that were raised in normoxic conditions regardless of treatment line. Generations in which O₂ significantly affects tracheal diameter are marked with an asterisk (P<0.05).