milk yield in lactation period

例句：

1. 1. The dairy industry contributes significantly to the country's agricultural sector.
   乳制品产业对该国农业部门的贡献显著。
2. 2.The farmers are trying to increase their milk yield to meet increased demand.
   农民们正试图提高他们的牛奶产量以满足增加的需求。
3. 3.The government has implemented policies to boost milk yield and improve nutrition in the country's rural areas.
   政府已经实施了政策，以提升牛奶产量并改善该国农村地区的营养状况。