A dip cup 10 comprises a cup 12 for receiving a teat, the cup 12 being connected or connectable to a supply of teat treating liquid including a foaming agent, foaming elements 34, 36 for mixing air and the teat treating liquid to produce foam, and a regulator device 16 for setting an air-to-liquid ratio. The regulator device 16 is selectable or adjustable based on the teat treating liquid, so that a specified air-to-liquid ratio is achieved.
