Lymphocystic Disease in Wild Croaker (Micropogonias furnieri) and Flounder (Paralichthys orbignyanus)

Lymphocystis disease has been reported worldwide in several species of freshwater fish and marine fish, naturally infected in the wild environment, or in intensive crops in farms. Nodular warty lesions of irregular surface were observed in the tegument and fins and mouth in a species of croaker (Micropogonias furnieri) caught in Cassino beach Rio Grande RS, Brazil and flounder (Paralichthys orbignyanus) caught in the city of San Clemente, Argentina. The skin lesions fragments were fixed in 20% buffered formalin, and the histological sections were stained with hematoxylin and eosin and Periodic Acid-Schiff (PAS), where microscopic alterations were visualized in the form of hyaline capsule with small basophilic structures in nodules and fibroblastic cells proliferation. The reported cases were based on the disease macroscopic findings characteristic of a lymphocystis disease, along with the histopathology, which confirmed the presence of the disease in the analyzed tissues.

Use of a species-rich and highly eutrophic tropical estuary in the South Atlantic by Pleuronectiformes (Teleostei: Acanthopterygii)

A total of 1,471 specimens of 16 species of flatfishes (Pleuronectiformes) were caught during 48 sampling campaigns between July 2005 and June 2007 at ten stations in Guanabara Bay, Rio de Janeiro, Brazil. Paralichthyidae was the dominant family, with Etropus crossotus as the dominant species. The outer stations, especially those on the western side of the lower estuary, were distinguished as a result of their higher abundance of flatfishes and number of species. The spatial distribution of E. crossotus and its population structure indicate that this species is an estuarine resident despite the apparent reduction in its area of occupation within the estuarine complex. Among the other species, nine were classified as marine stragglers (Achirus declivis, Bothus ocellatus, Cyclopsetta chittendeni, Etropus longimanus, Paralichthys orbignyanus, P. patagonicus, Syacium micrurum, Symphurus diomedeanus and Trinectes paulistanus) and three as estuarine opportunists (Bothus robinsi, Citharichthys macrops and Syacium papillosum); another three could not be classified due to the small number of captures or lack of previous data (S. tessellatus, A. lineatus and C. spilopterus).

Hemangioma esclerosante mandibular em Paralichthys orbignyanus: relato de caso

RESUMO Neste trabalho, descreveu-se o primeiro caso de hemangioma esclerosante registrado em um exemplar adulto do linguado Paralichthys orbignyanus. Produzido a partir de reprodução artificial, o peixe em questão tinha aproximadamente 10 anos de idade e fazia parte de um plantel de reprodutores. Ao ser retirado do tanque, notou-se a presença de lesão mandibular com escoriações e focos hemorrágicos. Amostras do tumor foram coletadas da mandíbula para análise histopatológica. Microscopicamente foi observada uma proliferação de numerosos vasos sanguíneos rodeados por um estroma conectivo denso. A etiologia dessa neoplasia é desconhecida, mas o fato de o exemplar ter permanecido por muitos anos em cativeiro pode ter contribuído para o surgimento desse tipo de lesão, devido aos choques mecânicos contra a parede do tanque que acontecem esporadicamente.