Histologically, immunohistochemically, ultrastructurally, and molecularly confirmed neosporosis abortion in an aborted equine fetus.

This research documents the first recorded case of an equine abortion caused by Neosporosis, an illness typically found in cattle. Using various strategies like histopathology, ultrastructural analysis, immunohistochemistry, and molecular investigation, this study provides evidence of Neosporosis being the reason behind the abortion of a horse fetus.

Research Methodology

• The study focused on an aborted female horse fetus that was 280 days into gestation. Samples from different parts of the fetus’ body, including the lung, heart, liver, skeletal muscle, tongue, brain, and placenta, were collected and preserved in formalin for diagnosis.
• Through histopathologic examination, the research identified disseminated Neosporosis with severe damage in lung, liver and heart tissues.
• Immunohistochemical analysis was carried out on these tissues using polyclonal anti-Neospora caninum rabbit antibodies. The protozoal tachyzoites found in the tissue samples reacted with these antibodies, providing more evidence of Neosporosis.
• On investigating the lung tissue under the transmission electron microscope, tachyzoites that resembled the protozoan parasite causing Neosporosis were found. The presence of numerous rhoptries was a distinctive feature of these tachyzoites.
• Lastly, molecular testing was carried out using Polymerase-chain reaction (PCR). Scientists amplified the rRNA gene internal transcribed spacer 1 (ITS1) of the Sarcocystidae family from the fetal DNA. A comparison of the ITS1 with sequences present in GenBank revealed a complete match to ITS1 sequences from three isolates of Neospora hughesi.

Implications of the Study

• The comprehensive process led to the conclusion that Neosporosis was the cause of the equine abortion. This result is noteworthy because Neosporosis is generally a condition causing abortion in cattle and is rarely observed in horses.
• This research may open a new perspective on evaluating other mysterious cases of equine abortions. It shows the need for further research on Neosporosis in horses and other, not typically affected, species.
• The study could influence future veterinary medicines and practices of prevention by identifying a new risk factor for equine miscarriages.