title: Rhabdomyosarcoma in a Silver Carp.
abstract: Rhabdomyosarcoma is a primitive neoplasm that originates from skeletal muscle progenitor cells. In a routine inspection of a cyprinid farm in southwestern Iran, an approximately 2-year-old female Silver Carp was observed to have a raised mass located on the dorsolateral surface just caudal to the head. Macroscopic examination revealed a firm irregular fleshy pink mass (5 × 4 cm, depth = 3 cm) that appeared to arise from the subcutaneous musculature. Histologic sections were prepared using routine methods and separate sections were stained with hematoxylin-eosin and Massons' trichrome. Microscopically, the tumor mass was composed of spindle cells that were densely packed and arranged in long interwoven bundles. The nuclei were vesicular and oval to elongated or cigar-shaped. Nuclear pleomorphism and multinucleate tumor giant cells were clearly evident. The neoplastic cell cytoplasm was eosinophilic with indistinct cell margins, and clear cross striations were observed in fibrils. The striated fibrils stained diffusely red with Masson's trichrome. This account represents the first reported occurrence of rhabdomyosarcoma in Silver Carp Hypophthalmichthys molitrix. Received July 10, 2015; accepted February 4, 2016.
authors.affiliation: a Department of Pathobiology, Faculty of Veterinary Medicine , Shahid Chamran University of Ahvaz, Campus Delivery, Building of Faculty of Veterinary Medicine , Golestan Boulevard , Ahvaz 61357-831351 , Iran.
authors.forename: Annahita
authors.initials: A
authors.lastname: Rezaie
authors.affiliation: b Department of Fisheries, Faculty of Marine Natural Resources , Khorramshahr University of Marine Science and Technology, Campus Delivery, Building of Faculty of Marine Natural Resources, Aliebne Abitaleb Boulevard , Khorramshahr 43175-64199 , Iran.
authors.forename: Seyed Mohammad
authors.initials: SM
authors.lastname: Mousavi
authors.affiliation: a Department of Pathobiology, Faculty of Veterinary Medicine , Shahid Chamran University of Ahvaz, Campus Delivery, Building of Faculty of Veterinary Medicine , Golestan Boulevard , Ahvaz 61357-831351 , Iran.
authors.forename: Mahshid Bagherzadeh
authors.initials: MB
authors.lastname: Ansari
mesh_terms: D000818:Animals; D002347:Carps; D005260:Female; D005393:Fish Diseases / Q000473:pathology*; D019042:Muscle Neoplasms / Q000473:pathology / Q000662:veterinary*; D012208:Rhabdomyosarcoma / Q000473:pathology / Q000662:veterinary*