Effect of transportation on the composition of bronchoalveolar lavage fluid obtained from horses

Abstract

Objective: To study the effects of extended transportation on the composition of bronchoalveolar lavage fluid (BALF) obtained from horses.

Animals: 30 horses (14 males, 16 females: 25 Thoroughbreds and 5 Thoroughbred-Arabian cross-breds; 27 to 30 months old) without a history or clinical signs of respiratory tract disease. Bronchoalveolar lavage was performed on nontransported control horses (groups 1 and 2) and transported horses (group 3).

Procedure: 20 horses were used to determine the effect of 41 hours of transportation on the composition of BALF (group 3). Bronchoalveolar lavage fluid was analyzed for recovered volume, number and distribution of nucleated cells, total protein and phospholipid concentrations, and phospholipid composition.

Results: Total number of nucleated cells in BALF from group-3 horses increased by approximately four-fold after transportation. Total protein concentration in BALF from group-3 horses also increased by approximately fivefold after transportation. Total phosphorus concentrations in group-3 horses decreased significantly from time 0 to immediately after transportation. In group-3 horses, the most characteristic change in composition of BALF after transport was a significant decrease in the concentration of phosphatidylglycerol.

Conclusion and clinical relevance: The decrease in phosphatidylglycerol concentration in BALF after transportation indicates a reduction in the quantity of surfactant. This change may reflect either a decreased production of surfactant by alveolar type II epithelial cells or an increased removal of surfactant from the alveolar region. It is likely that extended transportation resulted in a decreased concentration of surfactant in BALF. Such a decrease may reduce the pulmonary defence mechanisms in the alveolar region, possibly resulting in infection.