Vijayapoopathi Singaravel

The case report on cutaneous myxoma or invasive myxomatosis in Blackfin sea catfish ( Arius jella Day, 1877)

The presence of cutaneous myxoma is reported in a Blackfin sea catfish (Arius jella) from Vellar estuary, Parangipettai, southeast coast of India. The gross morphology revealed fleshy with gelatinous distended tumourous growths on both sides of the fish attached to the caudal peduncle region. Tumour overlying the epidermis was ulcerated, hyperemic and hyperchromatic. Histologically, the tumourous growth was characterized by bland spindloid cells embedded in an abundant myxoid extracellular matrix. The tumour masses were present within the dermis and covered with a thin attenuated layer of epidermis. Neoplastic cells were histochemically positive for alcian blue, argyrophilic nuclear organizer regions, Masson’s trichrome, periodic acid-Schiff, and toluidine blue and negative for Oil Red O. On the basis of the histological and histochemical findings, this tumour was diagnosed as cutaneous myxoma or invasive myxomatosis.

Prevalance and pathology of gastric tumours in Indian oil sardine (Sardinella longiceps) from Parangipettai coastal waters, southeast coast of India

Objective: To carry out the survey of prevalence of gastric tumour in Sardinella longiceps of Parangipettai coastal waters, south east coast of India for a period of one year. Methods: Fish samples were directly collected from fishermen and also from auction yard. The prevalence of gastric tumour, gross pathology, radiography, histopathology, morphometric and meristic characters were investigated. Results: A total of 31 stomach tumour infected individuals were collected during the study period. The gross morphology showed distended abdomen and the radiograph exhibited enlargement of stomach. Autopsy of the infected fish exhibited reddish multilobed tumourous growth on the stomach. Histologically, the tumour lesions were characterized by the differential rate of glandular epitheloid and mesenchymal cells, polymorphic and hyperchromatic nuclei and mitotic activity. No evidence of local invasion and distinct metastases were observed in these cases. Conclusions: The tumours were diagnosed as gastric adenoma, myofibroblastoma, lipoma and fibrosarcoma. Among them myofibroblastoma is highly prevalent.

Neoplasia in flat head grey mullet, Mugil cephalus Linnaeus, 1758 (Perciforms: Mugilidae): two case reports of myxoinflammatory fibroblastic sarcoma and leiomyoma

The presence of cutaneous neoplasms is reported in two cases of wild female grey mullet (Mugil cephalus) from Pazhayar and Parangipettai fish landing centre, southeast coast of India. A gross morphological examination case 1 revealed obvious reddish white, solitary and fleshy appearance of tumour located on behind the right-side of the anal fin, and the overlying epidermis was ulcerated, hyperemic and hyperchromatic. The tumour had a gelatinous consistency and released jelly-like matters. The tumour-affected case 2 revealed well-circumscribed, solitary and reddish fleshy appearance of tumour located on the left-side of the deep margin of the flank, the lesion covered with whitish-grey thin epidermal layer. Histolopathologically, the (case 1) tumour growth had distinct simulate bizarre tumour cells embedded in myxoid matrix with inflammatory infiltrates. The (case 2) tumour lesion showed interlacing bundles of spindled to elongated tumour cells with cigar-shaped nuclei. On the basis of the clinical and histolopathological findings, these tumours are diagnosed as myxoinflammatory fibroblastic sarcoma and leiomyoma.

Mandibular Odontogenic Fibrosarcoma in Pickhandle Barracuda (Sphyraena jello Cuvier, 1829)

The spontaneous occurrence of mandibular odontogenic fibrosarcoma is reported in pickhandle barracuda (Sphyraena jello) from Parangipettai fish landing centre, southeast coast of India. The gross morphology revealed reddish-white, fleshy distended tumours in and around the intraoral bone musculature. The necropsy examination showed no gross evidence of local invasion and distant metastasis into visceral organs. Histopathologically, tumours were characterized by abundant hyperplastic small spindle cells arranged into well-defined interwoven bundles. The spindle cells presented scant fibrillar cytoplasm, and oval to elongated hyperchromatic and pleomorphic nuclei. The ultrastructure of mandibular lesions was composed of differentiated fibroblasts with nuclei enveloped by a thin rim of cytoplasm with denser heterochromatin and lighter euchromatin. Mitotic figures were seen in high numbers of cells, telophase of the karyokinesis was observed. No virus particles were observed in the examined lesions. Based on the histological and ultra-structural findings, this tumour was diagnosed as mandibular odontogenic fibrosarcoma in S. jello.

Neoplasia in goldlined seabream, Rhabdosargus sarba (Forsskål, 1775)

Centre of Advanced Study in Marine Biology, Faculty of Marine Sciences, Annamalai University, Parangipettai, Tamilnadu, India PG and Research Department of Zoology, Government Arts College, C. Mutlur, Tamilnadu, India Department of Marine Science, Kulliyyah of Science, International Islamic University Malaysia (IIUM), Kuantan, Malaysia Department of Pathobiology, School of Veterinary Medicine, St George’s University, True Blue, Grenada