170. Most cows are milked by machine twice, sometimes three times, a day. The correct action of the milking machine is essential to cow comfort, optimum milking performance and udder health. Any machine that is not properly installed and maintained can cause significant welfare problems including discomfort and pain. Teat tissue may be adversely affected and, therefore, the functioning of the first line of the udder defence. This increases the risk of new mastitis infections. The machine can also have indirect effects in terms of milk hygiene and milk quality.
171. A correctly operating milking machine should minimise adverse effects on the condition of cows' teats. However, many milking machines are reported to be badly adjusted (British Mastitis Conference, 1997) and working inefficiently. The main faults are related to incorrect operation of the pulsation system, regulator and the design of the main air pipeline. Parlour installations rarely meet the current requirements of the British Standard for Milking Machine Installations (BS ISO 5707:1996), nor its predecessor.
172. In addition to physical damage to teats, the milking machine can actively transport bacteria to, and sometimes into, an udder quarter with the risk being greater with lower specification equipment and poorly installed and maintained equipment. An annual assessment of machine milking, which should include a dynamic (milking time) assessment, will measure the level of vacuum stability near the teat end, operation of cluster removal, milking routine and teat condition. Another important aspect of any assessment is the interaction between the operator, the cow and the machine.
173. The time spent by the cows in the parlour should be kept to a minimum and it is important that the parlour is big enough for the size of cows. Many of today's dairy cattle are substantially larger when compared to those when parlours were originally installed. As a result, many cows are squeezed into parlour stalls which are too narrow causing discomfort, fidgeting and often uneven milking due to poor cluster position. The latter predisposes to mastitis infection.
174. All staff, including relief milkers, who milk cows should be fully competent to perform all milking procedures. Ideally, formal training should be given. When undergoing training, staff must be supervised during milking by competent, trained operators.
175. The milker must be aware of the correct operation of the machine and be able to carry out simple checks at each milking . It is essential that the milking machine is functioning correctly in terms of vacuum level, pulsation rate and ratio (compatible with the design of clusters) and liner movement.
176. Where necessary, the dairy farmer should upgrade the specification of the milking machine to ensure that damage to teats and vacuum instability is within recommended tolerances. This will require specialist advice.
177. New installations or major refurbishments should be independently tested to ensure correct installation and operation. There are minimum levels specified in the British Standard for Milking Machine Installations.
178. The Welfare of Livestock Regulations 1994 require automatic equipment, such as milking machines, to be inspected daily and kept in good working order. The equipment should be tested and serviced as necessary (and as recommended by the manufacturer) by a competent person. Each year, a minimum of one full dynamic assessment should be carried out during milking. A record should be kept of the tests completed and a report should be provided to the farmer. Any recommendations made and remedial action to be taken should be recorded and an action plan put into place.
179. Buildings should be designed to enable the cows to enter and leave the milking parlour with a minimum of difficulty or stress. Collection and dispersal areas to and from the milking parlour should allow unhindered movement on non-slip floors. Stall dimensions should be suitable for the size of cattle being milked.
180. An independent generator, or other device, of a size and capacity for powering the machine and ancillary equipment, should be readily available in the event of electricity supply failure.