University of Tasmania
Browse

File(s) under permanent embargo

Understanding amoebic gill disease

journal contribution
posted on 2023-05-22, 03:11 authored by Wallach, M, Barbara NowakBarbara Nowak
Amoebic gill disease (AGD) is a severely debilitating disease, which mainly affects the salmonid industry. It causes high production losses worldwide, including Tasmania, where it is the main health problem in farmed Atlantic salmon. Without the use of control procedures such as fresh water bathing and/or by maintaining fish population densities at a level commensurate with proper hygiene, this disease can often lead to the death of over 50% of infected salmon. AGD is caused by the parasitic amoeba, Neoparamoeba perurans, which binds to and inhabits the gill epithelium of growing fish. Pathology is associated with severe epithelial hyperplasia, fusion of gill lamellae, lowering of oxygen tension and pH of the blood and eventual death of the fish. In order to understand this disease process, research has been carried out, to study the immune response of fish to primary and secondary infections, the genetic basis of resistance to infection as well as how the parasite binds to the host gill tissue and induces a severe host response. Results have shown that N. perurans contains within its surface glycocalyx, highmolecular- weight mucin -like glycoproteins. These surface mucins are immunodominant, according to studies showing that they are the major antigens recognized by antibody in serum from fish exposed to the parasite, as well as when immunized with either whole parasites or subcellular fractions. Thus far, attempts to vaccinate salmon using the purified, high-molecular-weight surface antigen (HMWA) have failed to induce significant protective immunity. However, these studies have greatly aided our understanding of the molecular basis of the amoeba binding and infection process.

History

Publication title

CAB Reviews

Volume

6

Pagination

1-6

ISSN

1749-8848

Department/School

Institute for Marine and Antarctic Studies

Publisher

CABI

Place of publication

United Kingdom

Repository Status

  • Restricted

Socio-economic Objectives

Aquaculture fin fish (excl. tuna)

Usage metrics

    University Of Tasmania

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC