In contrast to brown trout, grayling has become more widespread in Bavarian river systems (Kussmaul, 1986). The aim of this work was to find out if BKD can also be transmitted with these fish. The experimental trials show that this species can suffer from KD under laboratory conditions. Additionally, wild fish under natural conditions can at least carry the bacterium which supports the idea of a transmitter role. Therefore, grayling should be included in strategies of control.