Multiplex-PCR sensitivity test. Lane 1 – 250 bp ladder; lane 2 – mixture of different DNA (64.6 ng µl⁻¹ for E. tarda; 89.5 ng µl⁻¹ for V. alginolyticus; 110.8 ng µl⁻¹ for V. anguillarum; 24 ng µl⁻¹ for V. harveyi); lane 3 – mixture of different DNA (32.3 ng µl⁻¹ for E. tarda; 44.8 ng µl⁻¹ for V. alginolyticus; 55.4 ng µl⁻¹ for V. anguillarum; 12 ng µl⁻¹ for V. harveyi); lane 4 – mixture of different DNA (16.2 ng µl⁻¹ for E. tarda; 22.4 ng µl⁻¹ for V. alginolyticus; 27.7 ng µl⁻¹ for V. anguillarum; 6 ng µl⁻¹ for V. harveyi); lane 5 – mixture of different DNA (8.1 ng µl⁻¹ for E. tarda; 11.2 ng µl⁻¹ for V. alginolyticus; 13.9 ng µl⁻¹ for V. anguillarum; 3 ng µl⁻¹ for V. harveyi); lane 6 – mixture of different DNA (4 ng µl⁻¹ for E. tarda; 5.6 ng µl⁻¹ for V. alginolyticus; 6.9 ng µl⁻¹ for V. anguillarum; 1.5 ng µl⁻¹ for V. harveyi); lane 7 – mixture of different DNA (2 ng µl⁻¹ for E. tarda; 2.8 ng µl⁻¹ for V. alginolyticus; 3.5 ng µl⁻¹ for V. anguillarum; 0.8 ng µl⁻¹ for V. harveyi); lane 8 – mixture of different DNA (1 ng µl⁻¹ for E. tarda; 1.4 ng µl⁻¹ for V. alginolyticus; 1.7 ng µl⁻¹ for V. anguillarum; 0.4 ng µl⁻¹ for V. harveyi); lane 9 – mixture of different DNA (0.5 ng µl⁻¹ for E. tarda; 0.7 ng µl⁻¹ for V. alginolyticus; 0.9 ng µl⁻¹ for V. anguillarum; 0.2 ng µl⁻¹ for V. harveyi); lane 10 – mixture of different DNA (0.3 ng µl⁻¹ for E. tarda; 0.3 ng µl⁻¹ for V. alginolyticus; 0.4 ng µl⁻¹ for V. anguillarum; 0.1 ng µl⁻¹ for V. harveyi); lane 11 – control of the reaction, without DNA.