Ultrastructure of Sarcocystis buffalonis (Huong et al., 1997) infecting water buffaloes (Bubalus bubalis) from Egypt

Water buffaloes are infected with four Sarcocystis species, the macroscopic S. fusiformis and S. buffalonis, and the microscopic S. levinei and S. dubeyi. Few reports conducted on the presence of the newly described S. buffalonis infecting water buffaloes. In Egypt, no reports elucidate the ultrastructure of S. buffalonis. Herein, we examined the Egyptian water buffaloes for the presence of S. buffalonis, and studying their ultrastructure for the first time. Tissue samples were collected from 550 water buffaloes slaughtered at Mansoura abattoir, Egypt, and examined macroscopically, histologically and ultrastructurally. S. buffalonis cysts were noted in 8.72% out of the examined specimens. The prevalence of infection was higher in aged animals than in younger ones. Esophagus was the highly affected tissue followed by throat muscles and diaphragm, while no cysts were detected in the heart or tongue. Morphologically, the cyst wall was thick (3.5-7 µm) and palisade like with conical villar protrusions (3.8-7 µm in length) which bent laterally at an angle nearly 45° on the sarcocyst surface. Villar protrusions were constricted at the base (0.2-0.5 µm wide), expanded laterally in the middle region (0.5-1.0 µm wide), and tapered in the distal end. Bradyzoites measured 8-10.5 µm long and 0.5-1.5 µm wide.