Serosurvey of Toxoplasma gondii in North Atlantic marine mammals by the use of agglutination test employing whole tachyzoites and dithiothreitol.

Serum samples from North Atlantic populations of harp seal, Phoca groenlandica (n = 316), ringed seal, Phoca hispida (n = 48), hooded seal, Cystophora cristata (n = 78), and minke whale, Balaenoptera acutorostrata (n = 202), were tested for Toxoplasma gondii-specific IgG. The modified agglutination test (MAT) was slightly modified to be more user-friendly by replacing the 0.2 M 2-mercaptoethanol with 10 mM dithiothreitol. No positive samples were found at 1:40 dilution.