Controle de Neobenedenia melleni (MacCallum, 1927) (Monogenea: Capsalidae) em garoupa-verdadeira, Epinephelus marginatus (Lowe, 1834), cultivada em tanques-rede

Abstract

RESUMOO diagnóstico precoce de patologias no meio aquático constitui-se em uma necessidade vital para o sucesso dos cultivos. Considerados como parasitos oportunistas, surtos de infestação de monogenóides capsalídeos podem ocasionar mortalidades massivas gerando enormes prejuízos nos cultivos. Exemplares de garoupa-verdadeira Epinephelus marginatus (Lowe, 1834), com peso médio de 142,74 ± 38,65 g, apresentaram recusa da alimentação e sintomas como o escurecimento do corpo, natação errática, opacidade dos olhos, exoftalmia e hemorragias em diversas áreas do corpo. Alguns peixes apresentavam lesões no globo ocular e cegueira. Após análises dos peixes foi identificada a ocorrência do parasito Neobenedenia melleni. Este trabalho teve por objetivo testar o efeito de diferentes tratamentos por imersão em diferentes concentrações de formalina e água doce na erradicação de monogenoides capsalideos na garoupa-verdadeira. Foram testados três tratamentos em forma de banhos: T1 (água doce por 10 minutos); T2 (formalina: 1:2.000 por 10 minutos) e T3: (formalina: 1:4.000 por 10 minutos). Os tratamentos foram avaliados através de raspado de tecido epitelial, montados entre lâminas e lamínulas e observado ao microscópio de luz. Observou-se que nas condições testadas o T1 e o T2 foram eficientes na eliminação dos monogenóides capsalídeos na garoupa-verdadeira. The precocious diagnosis of pathologies in the aquatic way is constituted in a vital need for the success of the cultivations. Considered as parasites opportunists, infestations of monogeneans capsalides can cause missal mortalities resulting in enormous damages in the cultivations. Juveniles of dusky grouper Epinephelus marginatus (Lowe, 1834), with medium weight of 142.74 ± 38.65 g, presented refusal of the feeding and symptoms as the darkening of the body, erratic swimming, opacity of the eyes and hemorrhages in several areas of the body. Some fishes presented lesions in the eyeball and blindness. After analyses of the fish the occurrence of the parasite Neobenedenia melleni was identified. This work objective was to test therapeutic treatments seeking the monogenean capsalid eradication in juveniles of dusky grouper. Three treatments were tested in form of baths: T1 (fresh water for 10 minutes); T2 (formalin: 1:2,000 for 10 minutes) and T3: (formalin: 1:4,000 for 10 minutes). The treatments were evalueted by scraping epithelium tissue, mounted in slide glass and cover slip and observed by light microscope. It was observed that in the tested conditions T1 and T2 were efficient in the elimination of the monogeneans capsalids without presenting lethality in the dusky grouper. PALAVRAS-CHAVE

First record of Neobenedenia melleni (Monogenea: Capsalidae) in sea-farmed cobia (Rachycentron canadum) in Brazil

“…Th is is the fi rst report of N. melleni in cobia in Brazil. Th e specimens were similar to those described by Sanches and Vianna (2007) in groupers (E. marginatus) in Ubatuba, state of São Paulo, and more recently by Carvalho and Luque (2009) in swordfi sh (T. lepturus) from the coast of Rio de Janeiro. Specimens of N. melleni were deposited in the Helminthological Collection of Instituto de Biociências de Botucatu, Universidade Estadual Paulista (CHIBB No.…”

“…This parasite has been found in many species of ornamental marine fish and sea farming in different countries, thus demonstrating its low specificity to the hosts (BULLARD et al, 2003). In Brazil, Sanches and Vianna (2007) Capsalid monogeneans have a monoxenic, short life cycle, which allows epizootic outbreaks especially in hosts subjected to high stocking densities (THONEY;HARGIS JUNIOR, 1991). It has been demonstrated that water temperature influences the growth, maturity, egg production and infestation levels of Neobenedenia species (HIRAZAWA et al, 2010).…”

Metazoan parasite communities of Leporinus macrocephalus (Characiformes: Anostomidae) in cultivation systems in the western Amazon, Brazil

“…The generally higher indices of parasite prevalence, abundance and mean infection intensity observed in the earth tanks in comparison to the dams, can be explained by the higher density of fish in the earth tanks, which favors the dissemination of infectious forms of parasites (Sanches 2008).…”

First record of Neobenedenia “melleni” – like species (Monogenea: Capsalidae) in Goliath grouper Epinephelus itajara in Brazil

“…Other authors described N. melleni parasitizing different fishes in Brazil. Sanches and Vianna (2007) The symptoms found in E. itajara, such as body darkness, erratic swimming, exophthalmia and hemorrhage in different parts of the body were similar to those found in Epinephelus tauvina (Forskal) parasitized by capsalids. This subsequently resulted in secondary bacterial infection (JITHENDRAN et al, 2005).…”

“…Some parasites were collected and, subsequently fixed in formalin saline and processed for identification (AMATO et al, 1991). The treatment recommended by Sanches (2008) was used for removing the parasites; it consisted on immersing fish in freshwater for only five minutes. Due to the osmotic shock, the parasites died and detached from the fish, which made it possible to collect them at the bottom of the bath tank.…”