An occurrence of equine transport pneumonia caused by mixed infection with Pasteurella caballi, Streptococcus suis and Streptococcus zooepidemicus.

The study reports a case of equine transport pneumonia that led to acute death of a racehorse after long-distance travel. The disease was caused by a mixed infection of three bacteria types: Pasteurella caballi, Streptococcus suis and Streptococcus zooepidemicus. This is a first case of isolating P. caballi and S. suis from a racehorse in Japan.

Research Context

• The study focuses on an instance of equine pneumonia that led to an acute death of a racehorse in Japan. This condition manifested following long-distance transportation, indicating the disease as equine transport pneumonia.
• This instance is particularly interesting as the disease was found to have been caused by a mixed infection comprising three different bacteria – Pasteurella caballi, Streptococcus suis, and Streptococcus zooepidemicus.

Key Findings

• The mixed infection caused by three bacterial species was confirmed through immunohistological demonstration of the specific antigens of these bacteria in the pneumonic lesion.
• Pasteurella caballi, Streptococcus suis, and Streptococcus zooepidemicus were isolated from the lung at a high rate, corroborating the diagnosis of a mixed infection.

Significance

• This study is critical as it is the first report of isolating Pasteurella caballi and Streptococcus suis from a racehorse in Japan.
• The research indicates that long-haul transportation could increase the susceptibility of horses to pneumonia caused by the aforementioned bacteria.
• This discovery proves crucial to develop advanced treatment strategies to control the incidence of these bacterial infections and reduce the risk of transport pneumonia in racehorses.