The assembly (1) has a valve unit which is attached to a teat (2). A plug holder (11) is provided with a wedge surface. A retaining projection is provided in interior of container (18). The plug holder is attached to outer wall of container and the wedge surface of plug holder is connected to clamping projection so that retaining projection of the valve unit is pre-tensioned against the inner wall of container. A flange is provided between inner wall of container and retaining projection. An independent claim is included for method for attaching cattle trough valve assembly to container.
