There is provided a milking cluster comprising a plurality of teat cups (1), in which each teat cup comprises a flexible liner (3) for engaging about a teat of an animal to be milked, and has a head portion (6) provided with a mouth (7) through which the teat is engageable with the liner, and a nozzle means (13) for discharging treatment fluid into the head portion (6) of the liner. A distributor (111) for distributing treatment fluid to the nozzle means of the liners comprises an inlet (114) for treatment fluid and outlets (115) connected to the nozzle means (13) of the teat cups. The milking cluster is characterised by a safety valve (123) connected to the distributor inlet (114), said safety valve being actuable during a milking cycle to open a drain port through which the treatment fluid may flow to waste.
