Abstract: A milking device for milking of a dairy animal with teats includes a control unit, a milking device including milking cups, a robot arm to attach the milking cups to the teats of the dairy animal, a teat-detecting device to determine positions of the teats, including an outer optically permeable component, such as a lens or cover plate, and a cleaning device to clean the optically permeable component. The cleaning device is provided with a cleaning liquid supply and an application device to apply the cleaning liquid to the optically permeable component. The milking device includes a spraying device for spraying a teat-treating liquid on the teats. The application device is configured to apply cleaning liquid to the optically permeable component at least while the spraying device sprays the teat-treating liquid. As a result thereof, adhesion of the often sticky teat-treating liquid to the optically permeable component is efficiently counteracted.