Influence of short distance transportation on tracheal bacterial content and lower airway cytology in horses.

The study investigates how short distance transportation impacts the bacterial content in the trachea and lower airway cytology in horses. It was found that transportation, especially without hay, can increase neutrophil counts and potentially lead to neutrophilia in bronchoalveolar lavage fluid.

Objective and Methodology

• The primary goal of the research was to explore the influence of short distance transportation on airway mucus, cytology, and bacterial culture in horses. This was carried out in order to identify any potential biases that may occur in the diagnosis of airway diseases in referral centres.
• A total of eight healthy adult horses were studied using a prospective cross-over design. Samples were obtained while the horses were stabled and following 2.5 hours of transportation, both with and without hay.

Results

• The study found that neutrophil counts, percentages and frequency of neutrophilia in bronchoalveolar lavage fluid (BALF) all increased following transport without hay. This implies that the short distance transportation process can lead to an increase in neutrophils, white blood cells that fight infection, in the horses’ lower airways.
• Conversely, no significant effect was observed on tracheal cytology and bacterial count. This means that the transportation process did not significantly alter the cell studies in the trachea or the amount of bacteria present.

Interpretation and Implications

• This inflammation observed in lower airways, termed BALF neutrophilia, could develop solely as a result of transportation, perhaps due to stress or changes in environmental conditions related to the transport.
• Alternatively, this inflammation may be a result of interactions between repeated transports, ambient temperature, head position, or other environmental factors encountered during transportation. This highlights the potential for multiple factors to influence horse health during transportation
• The findings have implications for horse health during transportation and may influence practices for transporting horses to minimize adverse impacts on their respiratory health.