مطالعه مقايسه اي تشخيص ساركوسيستيس در لاشه گوسفندان ذبح شده در كشتارگاه تبريز

Comparative study on sarcocystis diagnosis in meat of slaughtered sheep in Tabriz

Sarcocystiosis caused by different sarcocystis species is a zoonotic protozoan infection with worldwide distribution in man and many species of animals. In the present work, four techniques were investigated for diagnosis of sarcocystis infection in slaughtered sheep in Tabriz, Iran. In the first, 400 sheep slaughtered in Tabriz slaughterhouse were selected randomly during a year. Then their esophagus, shoulder muscles, thigh muscles, diaphragm and heart were inspected using necked eye examination. In the second step, the infection was investigated in the meat of 150 carcasses of sheep by three techniques of, smear with or without staining and pepsin digestion. For digestion of muscles, the tissues were minced and poured in digestion medium containing pepsin, HCl and NaCl. The digestion was done at 40ºC for 60 min, and then the sediment was microscopically examined for presence of cystizoites. The percentage of macroscopic cysts were 24.7%, 16.2%, 17.7% 27%, and 2.2% for each muscles of esophagus, thigh muscles, shoulder muscles, diaphragm and heart respectively. Meanwhile the microscopic type found in 100% of the organs. However, the sensitivity of stained smear was less than pepsin digestion method but it is superior to non-stained smear method. In general, the pepsin digestion is found the most sensitive method for diagnosis of Sarcocystis in the meats of animals. Although 100% of sheep were found infected with Sarcocystis but the majority of the cysts were demonstrated microscopically. Means, the meat should cook sufficiently without considering the macroscopically meat inspection results.