Studies on <i>Amyloodinium</i> Infestation in European Seabass (<i>Dicentrarchus labrax.</i>) Fishes with Special Reference for Treatment

Abstract

Amyloodinium ocellatum, adinoflagellate which causes one of the most serious diseases of warm water marine aquaculture. The parasite produces a powdery or velvety appearance on infected fish, and the resulting disease is commonly referred to as "marine velvet," velvet disease, or Amyloodiniosis. The organism is a dinoflagellate ectoparasite and has been reported in a wide range of marine and estuarine fish. It is one of a very few organisms that can infect both teleosts and elasmobranchs (Alvarez-Pellitero, 2008). This makes it a concern for public aquaria. This ectoparasite can be found on gills and skin (body and fins) of host fish. It can cause devastating disease and mortality because the organism is able to reproduce quickly when fish are crowded, especially in closed systems. This parasite has a broad host and geographic range, causing fish mortalities in tropical and temperate environments. Rapid spread of the parasite and high mortality are common in cultured fish if the organism is not recognized and treated early in the course of an outbreak. One of the most important of the ectoparasitic protozoaisIn this respect, the present study was aimed to investigate the occurrence of Amyloodiniosis among cultured European seabass (Dicentrarchus labrax L.; Moronidae; Perciformes) fishes. This work was carried out on 1065 European seabass fishes of diffrerent life stages (546 fry-222 fingerling and 78 adults) which were collected in different seasons of the year. Cultured fish were collected from different marine farms in Egypt during the period from April 2015 to April 2016 and subjected to full clinical parasitological and histopathological examination studying the environmental stressors surrounding examined fish and their association with A.ocellatum infestation Study the ecological factors affects Amyloodiniosis. As well as examining the antiseptic activity of hydrogen peroxide against the ectoparasitic protozoan A.ocellatum as a trial for treatment.

Untitled

“…The primary preferred site of infection of A. ocellatum is mostly the gill epithelium of the host fish (Seoud et al, 2017). Damage to infested cells is related to the insertion of the rhizoids of the trophonts into the host cells causing focal erosion of the epithelium (Paperna, 1980).…”

Amyloodiniosis in aquaculture: A review

“…13 More recently, the treatment of European sea bass, with 100 and 200 ppm of hydrogen peroxide for 30 min significantly decreased the number of trophonts observed on the gills. 15 Hydrogen peroxide should be used within the therapeutic limits, as it can be lethal to the fish. Finally, although hydrogen peroxide reduced fish death associated with amyloodiniosis, it is unknown if tomonts remain viable after the treatment.…”

“…The dinoflagellate A. ocellatum is responsible for amyloodiniosis, a parasitological disease with a strong economic impact in temperate and warm water aquaculture, mainly in earthen pond semi-intensive systems. 2,[13][14][15][16] Amyloodiniosis is also considered a medium-severity disease in laboratory animals, regarding the effects on research. 17 However, even if it is a disease that affects more than one hundred farmed fish species in warm and temperate seawater, 18 there is a lack of available information on this disease.…”

Functional Additives in a Selected European Sea Bass (Dicentrarchus labrax) Genotype: Effects on the Stress Response and Gill Antioxidant Response to Hydrogen Peroxide (H2O2) Treatment

“…The use of biocide compounds is an extended practice in aquaculture production in order to eliminate microorganisms and other pathogenic agents in aquaculture facilities [1,2]. Among them, hydrogen peroxide (H 2 O 2 ) is a powerful oxidizer compound used against fish external parasites and bacteria [3][4][5] with proven effectiveness in treating diseases in European sea bass (Dicentrarchus labrax) [6,7]. However, this compound is an important source of reactive oxygen species (ROS), which may induce severe tissue damages, especially on those directly exposed to the surrounding environment [8,9].…”