Abstract: The invention relates to a milking device, which includes a milk-transporting conduit containing at least one teat cup arranged to be attached to a teat of an animal to be milked, and a milk hose to permit a transportation of milk from the teat to a milk-collecting member. The milking device also includes a pump device and a gas supply system. The pump device is connected to the milk-collecting member via the milk-transporting conduit. The gas supply system is arranged to support the transportation of milk by supplying a gas at an atmospheric pressure level. The gas supply system, in turn, includes a gas conditioning sub-system and a gas inlet member. The gas conditioning sub-system is arranged to receive an unconditioned gas, and in response thereto, produce a conditioned gas fulfilling at least one quality criterion. The gas inlet member is arranged to introduce the conditioned gas into the milk-transporting conduit and thus permit the transportation of milk.