Objective: Study on the macroscopic and microscopic characteristics of rumen cysticercosis of cattle.
Design: Case report.
Procedure: At routine meat inspection in Khorram-Abad slaughterhouse, in two indigenous cattle with generalized cysticercosis, the cysticerci with peripheral tissues were fixed in 10% formalin and were then examined for identification of microscopic characteristics. In order to study tissue lesions induced by parasite, the tissue sections were stained with H&E, PAS, Giemsa geners and Masson's Trichorome.
Results: In two indigenous cattle, 2 and 4 year-old with generalized cysticercosis, a number of cysticercus bovis were found between serous and muscle layer of rumen. Parasitologic and pathologic examinations of the cysticerci revealed they were cysticercus bovis having a diameter of 0.8-1 cm xOA-O.5 cm. A white, thin and translucent membrane through which the scolex of Taenia saginata was visible surrounded them. Internally a pale or light yellow fluid filled the cysticerci. Histopathologic examination revealed the cysticerci being located in loose connective tissues between
mesothelial layer and external muscle layer of rumen. A very slight inflammatory reaction around the cysts with infiltration of lymphoid cells especially small lymphocytes and edema were among lesions
causing a gap between connective tissues and muscle layers. Masson's trichrome stain showed that a fibrous capsule with a thin inner layer and a thick outer layer surrounds the metacestodes. The inner layer was composed of compact smooth muscle cells and the outer layer was dense connective tissue. There were no differences between the lesions induced by the metacestode in the heart and the rumen except that in the latter the cysts were more superficial. Clinical implications: Rumen could be a natural site location for C.bovis. This could cause mild pathologic changes very similar to those produced in other muscles. On the other hand because Tania saginata infection in human being is induced by consumption of row or uncooked infected muscle thus this could be born in man becomes infected with row or uncooked rumen. J. Fac. Vet. Med. Univ. Tehran. 58, 3: 267-270, 2003.