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Is this the future of dairy farming in the UK? Here almost 30,000 cows are housed under the roofs of one so-called mega-dairy farm in the United States.
In rural Indiana, this mega-dairy is called Fair Oaks Farm. Everyday 30,000 cows produce two million pints of milk from its 21 sheds.
At Fair Oaks, milking never stops. Each cow eats 100 pounds of food and drinks 30 gallons of water to produce 80 pints of milk in a single day.
Fair Oaks has become a popular tourist attraction, receiving 400,000 people each year at its visitor centre.
Peter Willes (left) tours the farm with Panorama reporter Paul Kenyon. Mr Willes is planning a mega-dairy in Nocton, Lincolnshire to supply UK supermarkets. "We care passionately about the animals but this is still a business," he says.
After milking, cows are led into sheds one quarter of a mile long. They never graze outside. The farm owners say the cows are happy and well cared for. Critics says these are not really farms, but factories.
British dairy farmer Tony Gillett is one of the visitors at the farm and he says the cows seem content on the mega-dairy; "You can see in their faces, you can see they're happy."
There are 80 births every day on Fair Oaks farm. The calves are kept in individual hutches - smaller than those permitted in the UK.
The first US mega-dairy opened over a decade ago. Critics claim small family firms have been forced out of business and grazing animals have disappeared from fields, but are consumers prepared to pay premium prices for milk to see smaller farms survive?
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