Oesophageal sarcocystosis in an Indian female buffalo (Bubalus bubalis) - A case study

Abstract

An adult female Murrah water buffalo (Bubalus bubalis) carcass from Cattle and Buffalo Farm, ICAR-Indian Veterinary Research Institute (ICAR-IVRI), Izatnagar, Bareilly, Uttar Pradesh, India (28°10'N and 78°58'E) was sent to Postmortem Examination Facility of Division of Pathology, ICAR-IVRI and necropsy was carried out. On systematic examination, large, opaque white, boiled rice-like cysts and typical fusiform shape with wide middle and tapered ends, and embedded in the muscularis externa, underneath the serosa and visible through the serosal surface of the oesophagus. They were easily separated from oesophagus. Sarcocysts were noticed in entire oesophagus from pharyngeal part to abdominal oesophagus. The cysts were of different size (ranges from 7-20 mm length and 2-5 mm width) with uniform shape. The contents of cyst showed crescent shaped bradyzoites and few metrocytes. On histopathological examination, cyst wall was thin and smooth with 1-3 pm thickness. Ground substance beneath the cyst wall contained metrocytes. Inner compartmentalization contained various intensities of bradyzoites. Hyaline degeneration and atrophy of oesophageal muscle fibers were noticed. In the present study, based on the distinctive shape (fusiform shaped with wide middle and tapered ends) and size (7-20 mm in length and 2-5 mm in width) of cysts and microscopic cyst wall thickness (thin and smooth cyst wall with 1-3 pm width), the sarcocyst was confirmed as macrosarcocyst of S. fusiformis.