Nitroblue tetrazolium reduction by neutrophils of newborn foals, adult horses, and a foal infected with Rhodococcus (Corynebacterium) equi.

This research looks at the function of equine neutrophils, which are immune cells found in horses, in newborn foals, adults, and a foal infected with the bacteria R. equi. It was determined through a nitroblue tetrazolium (NBT) test that there was no difference in results between newborn foals and adult horses. However, a foal infected with R. equi presented increased NBT reduction by neutrophils until a week before passing away.

Objective and Methodology

• The main objective of this research was to study the function of equine neutrophils in newborn foals, adult horses, and a foal infected with the bacterial pathogen, Rhodococcus equi.
• The researchers used the quantitative nitroblue tetrazolium (NBT) reduction test to analyze the neutrophil function. NBT is a yellow water-soluble dye used in laboratories to check for certain types of cellular activities, particularly those relating to immune response.

Findings

• The study found no significant difference in the NBT reduction test results between newborn foals and adult horses. This suggests that the function of equine neutrophils in handling cellular activities remains consistent across different ages.
• Interestingly, the research noted a significant increase in the spontaneous NBT reduction by neutrophils in a foal naturally infected with R. equi. The NBT reduction rate remained elevated until a week before the foal’s death.

Implications

• The study’s findings suggest that an infection with R. equi can significantly alter the behavior of equine neutrophils. This may affect the host’s defense mechanism against this bacterium, and lead to severe illness or even mortality, as observed in the studied foal.
• Further research is essential to fully understand the relationship between R. equi infection and the altered immune response in horses. This could lead to better preventive measures and treatment options for equine diseases caused by R. equi infection.