University of Tasmania
Browse

File(s) not publicly available

Biofouling as a reservoir of Neoparamoeba pemaquidensis (Page, 1970), the causative agent of amoebic gill disease in Atlantic salmon

journal contribution
posted on 2023-05-16, 13:26 authored by Tan, CK, Barbara NowakBarbara Nowak, Hodson, SL
Amoebic gill disease (AGD) is currently the most important disease affecting the Tasmanian salmonid industry and is caused by a marine amoeba, Neoparameoba pemaquidensis (Page, 1970). In this study biofouling communities on salmon cages were surveyed for the presence of the disease agent over a period of 4 months. Malt-yeast-seawater (MYS) agar plates were used to culture N. pemaquidensis with its presence confirmed by immunofluorescent antibody test (IFAT). Positive percentages of categorised samples ranged from 0% to 55%. The survey detected the presence of N. pemaquidensis on a number of macrofouling species (in particular bryozoan Scrupocellaria bertholetti and solitary ascidian Ciona intestinalis), and in microfouling and water samples. High percentages of positive IFATs occurred in microfouling aggregates, the solitary ascidian, C. intestinalis, and centrifuged water samples. No positive IFATs occurred from samples of Caprella sp. The presence of N. pemaquidensis was sporadic and varied in species and over sampling month. Experimental exposure of Atlantic salmon, Salmo salar, to lightly fouled netting was conducted to assess the potential for microfouling to act as a source of infection. No signs of the disease were detected in fish exposed to lightly fouled netting treatments, while 100% of positive control fish were infected and had an average of 4.24 ± 1.79 amoebae per field of view in IFAT of mucus smears. When combined with N. pemaquidensis loads in the water column, the loads of amoebae in biofouling communities may contribute to disease outbreaks. Thus, biofouling should be considered a risk factor for AGD outbreaks. © 2002 Elsevier Science B.V. All rights reserved.

History

Publication title

Aquaculture

Volume

210

Pagination

49-58

ISSN

0044-8486

Department/School

Institute for Marine and Antarctic Studies

Publisher

Elsevier

Place of publication

Netherlands

Repository Status

  • Restricted

Socio-economic Objectives

Fisheries - aquaculture not elsewhere classified

Usage metrics

    University Of Tasmania

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC