Heterobilharzia americana infection in a Grant’s zebra (Equus burchelli boehmi).

The research presents the first recorded case of a Grant’s Zebra being infected with Heterobilharzia americana, a parasitic trematode that primarily infects wildlife and occasionally dogs and horses in southeast U.S. The infection was detected post-mortem in the zebra’s liver after an accidental traumatic death.

Introduction and Background

• This research discusses a unique case of Heterobilharzia americana infection in a Grant’s Zebra, a condition typically seen in wildlife, domestic dogs and horses within the southeastern region of the United States.
• Heterobilharzia americana is a trematode parasite that belongs to the Schistosomatidae family. Trematodes are a class of flatworms, many of which are parasitic.

Case Presentation

• The report is based on a post-mortem analysis of a Grant’s Zebra (Equus burchelli boehmi) that died from a traumatic accident. While the death was accidental, the presence of this parasite was incidentally discovered in the liver parenchyma, the functional tissue in the liver.
• This presents the first known case of this parasite infecting a Grant’s Zebra, expanding our knowledge about the range of hosts this parasite can infect.

Diagnostic and Molecular Analysis

• The identification of the parasite was achieved through histopathological observation, which involved the microscopic examination of H. americana eggs in the liver tissue of the deceased zebra.
• Furthermore, molecular analysis was conducted on a part of the parasite’s small subunit ribosomal RNA gene. The DNA sequences obtained from this analysis were perfect matches with sequences from parasites found in domestic horses, confirming the identity of the parasite as H. americaria.

Conclusion and Significance

• The infection of H. americana in horses is considered rare but it is hypothesized that such infections might be underdiagnosed.
• This report highlights the need for further research into the range of hosts for the H. americana parasite and the potential for underdiagnosis in both domestic animals and wildlife.