Cows have been around people for some time.

牛作为人类的家畜已经有相当的长一段时间了。

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One reason this may be so frequently found is because cows have been selectively bred this way to increase the protein content of the cow-milk (a quality desired by dairy producers). 9

其原因之一可能因为牛是通过选择性繁殖的方式来提高牛奶的蛋白质含量（乳品生产者所期望的品质）的。

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Dozens of animals have been cloned since that first lamb—mice, cats, cows and, most recently, a dog—and it's becoming increasingly clear that they are all, in one way or another, defective.

自从第一只羊被克隆以来，已经有几十种动物被克隆了，包括老鼠、猫、牛和最近的一只狗；而且越来越明显的是，这些动物都有这样或那样的缺陷。

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Cows have been milked, curds separated, moulds turned and cheeses salted.

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For centuries cows have been sacred to Hindus.

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To solve for the bad situation, dairies have been sending cows to slaughter prematurely, rather than paying to keep them producing, says William Snell, of the Department of Agricultural Economics, University of Kentucky.

FORBES: Dairy