This study aimed to determine and identify Sarcocystis spp. infection in sheep and goats in Misan governorate, Iraq. samples from oesophagus, diaphragm, tongue, and heart muscles were examined histologically for microscopic and macroscopic cyst , 70 out of 90 sheep 77.78 % had microscopic thick walled sarcocysts with mean 53 ×24.72 μm diagnosed as Sarcocystis tenella while 25 out of them 27.78 % had microscopic thin-walled sarcocysts with mean 49.45×33 μm diagnosed Sarcocystis arieticanis , esophagus showed the highest infection rate above all organs examined for thick – walled Sarcocystis while diaphragm was the highest for thin –walled Sarcocystis , the heart was the lowest infected organ for both type as 27.78% and 3.33% respectively . In goats 50 sample examined revealed 20 infected with thick walled sarcocysts only with different in distribution according to organs being high in esophagus 40% and lowest in heart 16% with mean measurement 60.61 × 37.75 μm diagnosed as Sarcocystis capracanis.
