Livestock farming does the most damage.

其中畜牧业危害最大。

Raising cattle is the most important kind of livestock farming.

养牛是最重要的一种畜牧业。

Livestock farming is one of the biggest causes of nitrogen pollution, it adds.

该研究还补充道，畜牧业是导致氮污染的最大元凶之一。

Improving livestock farming is important because of meat's growing share in the world's diet.

提高畜牧业很重要，是因为肉类在世界饮食份额上的增加。

Previous poor living conditions, people crowded in a small room, and with livestock farming.

以前的生活条件很差，人们拥挤在很小的房间里，而且用家畜农耕。