Production, characterisation and diagnostic use of antisera to southern bluefin tuna (Thunnus maccoyii Castelnau) immunoglobulin

Sheep polyclonal antisera and one monoclonal antiserum (mAb) were prepared against purified southern bluefin tuna (Thunnus maccoyii Castelnau) immunoglobulin, and also rabbit polyclonal antisera were prepared against isolated immunoglobulin H chains. Activity and specificity were determined in immunoblots following SDS-PAGE in reducing and non-reducing conditions. In reducing conditions, the mAb and rabbit antisera reacted specifically with H chains of purified SBT Ig, and only with bands consistent with H chains in sera from other Thunnus spp. No cross-reactivity with reduced serum from any other teleost was found for the mAb, and only minimally for the rabbit antisera, but sheep antisera were less specific and reacted with bands other than those attributable to immunoglobulin. The antisera were used in serological assay development and detected the presence of infection with the blood fluke, Cardicola forsteri, a recently described pathogen of farmed southern bluefin tuna. © 2001 Elsevier Science B.V. All rights reserved.