Dairy farming

The UK dairy industry
In June 2007, the UK dairy herd was estimated at two million animals. Since 1995, the number of UK dairy farms has fallen by around 43 per cent, but average herd sizes have actually risen during this time from 71 cows in 1994 to 92 animals in 2004. Similarly, average milk yields have also risen from 5,299 litres per cow in 1994 to 6,770 litres per cow in 2005 (figures from Defra). Future trends suggest herds will get larger with fewer farmers staying in the industry.
 

Dairy farms in the UK have traditionally been located in the West of the country where there tends to be more rainfall and it is easy to grow grass and other forage crops for the cattle to eat. However, over time, more productive dairy cows have been bred, and grass is no longer as important as a food source in some areas. Because dairy cows can digest many other vegetable-based sources of food, larger dairy farms have been able to develop in some of the drier parts of the UK such as East Anglia, using crops such as maize and lucerne.

Housing and diet
Many dairy cattle are housed during the winter period, when grass is not growing. Some high milk-yielding herds may be housed all year-round (known as ‘zero-grazing’), and have fresh grass cut in the field and taken to the animals, or they are fed a mixed ration of a number of different ingredients such as maize or grass silage. It is often easier to control the amount of nutrients the animals get using this system compared with grazing.

Two types of housing system are generally used.
 

• Loose housing in which the cattle can freely move around inside a building, which must be at least partly bedded to give the cattle a lying area.
   
• Cubicle housing where the building has lots of separate ‘cubicles’ (at least one per cow), divided by barriers, and cows can freely enter, lie-down in, and leave them.
   

On some farms cattle may also be provided with additional ‘loafing’ areas for exercise.

Milking
For milking the cattle are moved to a collecting yard, and from there they enter the milking parlour, of which there are a number of different designs. Robotic milking machines have been developed and are also used on some farms. These automatically connect to the cows' teats, and can be used to provide the cows with a ‘self-service’ facility to allow them to choose when they want to be milked. This also allows the stockperson more time to observe the animals.

Working lifecycle of the dairy cow
Dairy cattle will normally have their first calf at two years of age, and will be milked two or three times per day for 10 months with a two month rest before calving again. In the UK, the average working lifespan of a dairy cow is around four lactations (milk-producing periods), and hence many dairy cows are culled when they are relatively young.