Development of Strongylus vulgaris-specific serum antibodies in naturally infected foals.

This research analyzed the development and behavior of Strongylus vulgaris (a harmful helminth parasite) specific antibodies in naturally infected horse foals over a one-year period. The study was able to track the presence of these antibodies during the six-month prepatent period using a newly developed serum ELISA.

Overview

• The research was focused on tracking the presence and development of S. vulgaris-specific antibodies in horse foals over a year.
• A serum ELISA (Enzyme-Linked Immunosorbent Assay) is employed to detect S. vulgaris-specific antibodies during the six-month-long prepatent period.
• Twelve foals born from a consistent population of horses, which have been maintained without anthelmintic intervention at the University of Kentucky since 1979, were used.
• Weekly serum samples were taken from the foals for monitoring.

Findings

• Nine out of the twelve foals were chosen for necropsy at different points between 90 and 300 days.
• During the necropsy, the species and stage of Strongylus spp. and Parascaris equorum were identified. Strongylus spp. were found to be highly prevalent.
• There was a significant interaction noted between the age of the foal and the ELISA results, indicating that age could have a significant influence on the immune system’s reaction to the parasite.
• All foals initially had antibodies directed towards S. vulgaris from the colostrum (first milk after giving birth), but remained ELISA negative during their first three months of life.
• The birth date of the foal was significantly associated with the ELISA results. The result indicates that there could be birth date-dependent differences in parasite exposure.
• One foal remained ELISA-negative throughout the study, which lasted 30 weeks.

Conclusions

• The study indicates a high correlation between the presence of S. vulgaris larvae and the ELISA test values.
• A substantial three-way connection was observed between the burdens of S. vulgaris, S. edentatus, and P. equorum.
• The experiment showed that the ELISA values hit a plateau, followed by a decline that corresponded with S. vulgaris larvae leaving the bloodstream and migrating back to the intestine.
• This decline in ELISA values potentially suggests the lifecycle stages of the S. vulgaris parasite.