milk duct

例句：

1. 1. The milk ducts in the cow's mammary gland are responsible for the flow of milk from the cow to the baby.
   牛的乳腺导管负责将牛奶从牛体输送到婴儿。
2. 2. During pregnancy, the milk ducts in the mother's breasts expand to allow more milk to be produced.
   在怀孕期间，母亲的乳房中的乳管会扩张，以产生更多的奶水。
3. 3. The milk ducts can become blocked or damaged, which can lead to a decrease in milk production.
   乳管可能会堵塞或受损，导致奶水产量下降。