| Characterization of pulmonary surfactant in avian respiratory systems have been somewhat limited. In this study, pulmonary surfactant was removed from both the whole respiratory system and the posterior thoracic air sacs of the common pigeon, Columba livia. Surfactant was found to be present in the air sacs as well as the whole respiratory system. Air sac surfactant had a dramatically different composition from that of the whole respiratory system of the pigeon. This may be due to a difference of surfactant function in the air sacs. Because of their thin and compliant nature, the composition of air sac surfactant, high in unsaturated phospholipids, may act as an anti-glue to prevent the epithelial walls of the air sacs from adhering when compressed. In addition, pigeon surfactant composition was compared to literature values from a reptile and a mammal to determine whether phylogeny or physiology plays a greater role in determining the composition of pulmonary surfactant. |
