A case of transplacental transmission of Theileria equi in a foal in Trinidad.

The research article explores a unique case of transplacental transmission of Theileria equi, a parasite causing equine piroplasmosis, from a mare to its foal in Trinidad.

Objective of the Study

• The study aimed to investigate and document a case of Theileria equi infection in a newborn foal, a rarely reported transmission mode for the parasite. The infection is suspected to have been transmitted transplacentally from the mare to the offspring.

Methodology of the Study

• The investigation began when a thoroughbred foal was diagnosed with equine piroplasmosis just 10 hours post-birth. Blood smear tests conducted showed high parasitaemia (63%) of piroplasms, indicative of T. equi infection.
• To confirm T. equi presence, the researchers used molecular methods. They extracted DNA from the foal and the mare’s blood, amplified the 18S rRNA gene for Babesia/Theileria, and subjected the amplified products to a reverse line blot hybridization assay (RLB).

Findings of the Study

• The RLB test confirmed the presence of T. equi DNA in the foal. The mare, despite being RLB negative, was also confirmed to be infected with T. equi. This infection was detected using a nested PCR and sequence analysis method.

Conclusions and Recommendations

• The research concluded that equine piroplasmosis could be transmitted transplacentally, suggesting that T. equi infection in foals could be misdiagnosed as neonatal isoerythrolysis, another cause of severe jaundice in newborn foals.
• The researchers recommended that routine screening for equine piroplasmosis should be established for foals showing post-partum jaundice, particularly in areas where the disease is endemic like Trinidad. They emphasized that molecular methods could be employed for accurate diagnosis.