这里的关键词是“谷物饲养”。

The key word in all this is "grain fed".

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相比较，谷物饲养出的牛肉每大卡产生（13.82克），猪肉（9.03克）和羊肉（25.97克）的排放物。

By comparison, grain-fed beef (13.82g), pork (9.03g) and lamb (25.97g) cause far more emissions.

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同样，当芝加哥的研究者研究鱼类时，他们发现养殖对虾比谷物饲养的羊肉和牛肉有更高的碳强度，每大卡30.86克。

Equally, when the Chicago researchers looked at fish, they found that farmed prawns were even more carbon-intensive than grain-fed lamb and beef, with 30.86g per Kcal.

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