Muscular coenurosis in a wild rabbit

Rabbit coenurosis is caused by the larval stage of Taenia serialis, a tapeworm of the dog and other carnivores. This larval stage or Coenurus serialis is found chiefly in the subcutaneous tissue of rabbits. Coenurus contains multiple protoscoleces, which distinguishes it from a cysticercus, which contains a single protoscolex. This article is the first reported case of Coenurus serialis in a wild rabbit from Shahrekord suburbs, Iran that describes its macroscopic and microscopic features and associated lesions. Grossly, a 4-cm-diameter, fluid-filled cyst with white clusters of protoscolices was observed in the hip area muscles. There were 147 protoscolices attached to the internal layer of the cyst. Histopathological examination of the affected muscles revealed sections of multiple protoscolices, hooklets and numerous calcareous corpuscles. The muscular tissue surrounding the cyst was compressed and atrophied. Proliferation of connective tissue, inflammatory cells mostly lymphocytes, plasma cells and macrophages were present in these regions. The cyst was identified as coenurus of Taenia serialis based on morphological appearances, intermediated host and affected muscles. Due to the presence of coenurus forming Taenia species in Iran and its potential ability as a zoonotic disease and in creating of economic losses in animal husbandry, further attention to control of coenurosis is recommended and emphasized.