Pulmonary surfactant in normal foals and foals with bacterial pneumonia
Pulmonary surfactant plays an essential role in reducing surface tension forces at the air-liquid interface of the lung and in host defense mechanisms. To investigate the effect of bacterial infection on pulmonary surfactant in the foal, the composition and function of surfactant in normal foals and foals with experimentally induced pneumonia by 'Klebsiella pneumoniae' were characterized. Overall, the composition of healthy foal surfactant is similar to the adult horse and to other species. The surfactant alterations associated with pneumonia induced by 'K. pneumoniae' were, however, minor relative to the alterations associated with bacterial pneumonia reported in other species. 'In vitro' studies evaluating the response of equine surfactant to bacterial components, proteins and inflammatory mediators, in addition to investigation of the 'in vivo' response to other bacterial causes of pneumonia in the foal, are required to further understand the role of surfactant in pneumonia in this species.