During his two years of research, Kardashian followed the trail of milk from the small pastoral farms that dot the countryside around his Vermont home to the industrial dairy cattle plants of the Midwest, and 12, 000 years back in time to the dawn of dairy farming.

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The road rises, dips, twists, and turns along the eastern shore as it passes the occasional house, amid small herds of dairy and beef cattle behind barbed wire fences.

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Over the years the farm was used for raising goats and cattle, dairy farming, and growing corn.

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In Cotacachi, 10km north of Otavalo, craftspeople have been making leather products for hundreds of years, owing to the town's position surrounded by cattle and dairy farms.

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Dairy farmers have had to keep cattle under cover almost every day since October, spokesman James Watts said.

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"Bovine TB continues to spread at an unacceptable rate, leading to the slaughter of thousands of cattle and ongoing misery for our dairy farmers, " said Farming Minister David Heath.

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Karen Hogan, who keeps the breed and runs a micro dairy at Trenow, was looking after Mr Babcock's cattle when the dogs attacked.

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The Shrewsbury and Atcham MP spoke of the "devastating" impact on dairy farmers and their families when "whole herds" of cattle are taken away to be killed.

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Up to 18% of US cattle are thought to have the disease which mainly affects dairy herds.

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To the untrained eye like my own, Dean's cattle look in rude health but he shakes his head and explains, with their restrictive diet, his dairy herd is producing less and poorer quality milk.

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