Under normal circumstances, a cow will give birth after a gestation period of about 280 days. A series of changes will occur in the reproductive organs and pelvic parts of cows in the pre-parturition period, and the cow's mental state and general condition will also change to meet the needs of expelling fetuses and feeding newborn calves. Mastering the signs of delivery of cows can predict the time of delivery in order to do a good job of delivery and postpartum care. The harbingers of cow delivery are mainly manifested in the following aspects.

(1) Breast enlargement

The udders of a cow begin to swell about 15 days before delivery, and the udders develop rapidly, almost double the size of the original. 2 to 3 days before delivery, the udders are swollen, the skin is tight, the base of the nipple is swollen, and the nipple becomes thick. The two nipples squeeze out a viscous, light yellow juice. When milky milk can be expressed, you will calve after another 1 to 2 days.

(2) Swelling of the vulva

In the later stages of pregnancy, the cow’s labia gradually swells, becomes soft and folds flat. One to two days before calving, clear mucus flows out of the vulva.

(3) Pelvic changes

About 10 days before delivery, the ligaments of the cow's pelvis became loose and soft, and the tail root collapsed on both sides to allow the fetus to pass. One to two days before delivery, the pelvic ligaments were fully softened, and the muscles on both sides of the tail base collapsed obviously, and both sides of the pelvis were soft when touching. When you hold the root of the tail and move it up and down, you will obviously feel that the root and tendon are easy to move up and down.

(4) The cow is uneasy

Before giving birth, cows will lie down from time to time, look back and look at their abdomen, walk back and forth, and urinate frequently. At this time, you should be ready to accept production.