Location: Animal Parasitic Diseases LaboratoryTitle: Histologically, immunohistochemically, ultrastructurally, and molecularly confirmed neosporosis abortion in an aborted equine fetus
|ANDERSON, JOSEPH - Naval Medical Research Center|
|ALVES, DERRON - The Joint Pathology Center (JPC)|
|CERQUEIRA-CEZAR, CAMILA - Non ARS Employee|
|DA SILVA, ANDRESSA - Non ARS Employee|
|MURATA, FERNANDO - Non ARS Employee|
|NORRIS, JAMIE - University Of Kentucky|
|HOWE, DANIEL - University Of Kentucky|
Submitted to: Veterinary Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/19/2019
Publication Date: 5/3/2019
Citation: Anderson, J.A., Alves, D.A., Cerqueira-Cezar, C.K., Da Silva, A.F., Murata, F.H., Norris, J.K., Howe, D.K., Dubey, J.P. 2019. Histologically, immunohistochemically, ultrastructurally, and molecularly confirmed neosporosis abortion in an aborted equine fetus. Veterinary Parasitology. 270:20-24. https://doi.org/10.1016/j.vetpar.2019.04.009.
Interpretive Summary: Toxoplasmosis, caused by the single celled parasite, Toxoplasma gondii, continues to be a public health probem. In addition to causing severe disease in humans, toxoplasmosis also causes abortions in livestock and mortality in many other hosts. Neosporosis, caused by a parasite Neospora caninum, is relatively a newly recognized entity. Until 1988, N. caninum was misdiagnosed as T. gondii. In 1988, J.P. Dubey (an ARS researcher) in collaboration with others, cultivated and named the parasite N. caninum. Neosporosis is now considered the most important cause of abortion in cattle worldwide. Differential diagnosis of neosporosis from toxoplasmosis is often difficult. In the present paper, the authors report first confirmed Neospora abortion in a horse. This paper will be of interest to parasitologists, biologists and veterinarians.
Technical Abstract: Neosporosis is a common cause of abortion in cattle worldwide but is rare in horses. Here, the first case of histologically, ultrastructurally, immunohistochemically-, and molecularly-confirmed equine abortion caused by neosporosis is reported. Samples of lung, heart, liver, skeletal muscle, tongue, brain, and the placenta from a female fetus aborted at 280 days of gestation were fixed in formalin and submitted for diagnosis. Histologically, there was disseminated neosporosis with severe lesions in lungs, liver and the heart. Protozoal tachyzoites in all tissues reacted with polyclonal anti-Neospora caninum rabbit antibodies. Transmission electron microscopic observation on lung tissue revealed tachyzoites consistent with Neospora, including many rhoptries. Polymerase-chain reaction (PCR) using primers designed to amplify the rRNA gene internal transcribed spacer 1 (ITS1) of the Sarcocystidae was performed on DNA extracted from fetal tissues. Comparison of the ITS1 amplified from the foal tissue to sequences available in GenBank revealed 100% sequence identity to the ITS1 from three isolates of Neospora hugh