Sudden death in a mare due to a malignant lymphoma.

The research paper tells the story of a Thoroughbred mare that suddenly died due to complications caused by malignant lymphoma.

Overview

The study focuses on the swift death of an 11-year-old Thoroughbred mare. Despite being treated for being possibly infested with strongyles, the mare suddenly died after being found sweating and lying down. The mare was restless, had a temperature of 100°, and had weak abdominal sounds and pale mucous membranes when first presented for examination.

Examination and Autopsy

• During an autopsy, various changes in the mare’s body were noted. The mucous membranes had turned white, with no blood discharge from any body orifice. Additionally, the muscles turned a pale grey.
• Further investigation revealed roughly 8 litres of dark, thick blood in the mare’s abdominal cavity. The source of this was found to be from an enlarged and fragile right ovary that had ruptured and bled out directly through the ovarian artery.
• Also noted was an enlarged spleen, with only a small portion appearing normal. A significant finding was a series of soft, crumbly nodules, reaching up to 2 cm in diameter, that were spread all throughout the spleen. Several other nodules were also found in the lungs and diaphragm muscle, with significant lesions found in the left psoas muscle.
• The mare’s left ovary also contained a nodule similar to the lesions found in other regions of the body. Although the kidneys and liver appeared to have no gross abnormalities, sections of all the lesions were taken for closer examination.

Conclusion

• The thorough examination and subsequent histopathological evaluation of all the sections were conducted by the Animal Research Institute, Yeerongpilly. Eventually, it was determined that the cause of the mare’s sudden death was due to a reticular cell type malignant lymphoma.
• Notably, the spleen was the only lymphoid organ to be severely affected with the largest splenic lesions. The researchers speculate that the lymphoma may have originated from the spleen. The spleen isn’t a typical site for metastases, thereby hinting at the likelihood that the primary lesion might’ve been sitting within the organ.