Prevalence of Sarcocystis in camels (Camelus dromedarius) from Al-Ahsa, Saudi Arabia.

The oesophagus, diaphragm and heart of 103 camels slaughtered at Al-Ahsa abattoir were investigated for infection with sarcocysts. Sarcocystis cysts were found in 91 camels (88.35%): in the diaphragm of 79.6%, oesophagus of 72.8% and heart of 71.8%. Two morphologically distinct sarcocysts were found. Thin-walled cysts (141-400 x 70.5-188 microns) were in all the three indicator organs while the thick-walled cysts (170-194 x 117.5-188 microns) were only found in the oesophagus. Experimental feeding of four cats and two dogs with sarcocysts-infected meat showed that cats were refractory to the infection while dogs excreted Sarcocystis sp. sporocysts (10.7-14.3 x 8.3-10.7 microns mean, 13.2 +/- 0.32 x 9.4 +/- 0.20 microns) after a prepatent period of 9-10 days. It was concluded that dogs may be the final host of both types of sarcocysts or that one of these cysts develops in dogs while the other one uses other carnivores living in the desert as the final host.