In dairy cow production, due to the lack of relevant scientific feeding and management techniques by farmers, the dystocia rate of dairy cows has increased, causing unnecessary economic losses to dairy cow production. The direct causes of dystocia in cows are divided into maternal and fetal causes.

Maternal causes: calving cows suffer dystocia due to narrow birth canal, insufficient labor or improper exercise, causing uterine torsion. When observing cows with B-ultrasound, it can also be seen that the birth canal of cows is very narrow. Birth canal stenosis is divided into soft birth canal stenosis and hard birth canal stenosis. Soft birth canal stenosis refers to incomplete opening of the soft birth canal, such as the cervical opening is not open or not fully opened, vaginal soft tissue stenosis and incomplete opening of the vulva fissure. This kind of dystocia can be completely diagnosed by using B-ultrasound for cows. Hard birth canal stenosis refers to incomplete opening of the hard birth canal, such as narrow uterine cavity, non-opening of pubic symphysis, incomplete opening of sacroiliac joint, tense sacroiliac ligament, non-depression of gluteal muscles, poor activity of tail root and small range of activity.

Insufficient labor refers to the cow's lack of effort and contraction force when calving. The contraction force of the abdominal muscles is weak, and the intra-abdominal pressure is low, which is not conducive to the delivery of the fetus, resulting in dystocia. When the contraction begins, the uterus gradually tightens and shrinks to facilitate the delivery of the fetus. If the uterine muscle contraction force is insufficient, it will lead to dystocia.

Uterine torsion The uterus twists in the abdominal cavity, causing the uterus to twist into a rope, resulting in the inability to deliver the fetus and causing dystocia in the cow. When observing the cow with B-ultrasound, it can be seen that the shape of the cow's uterus is abnormal.

link: https://www.bxlimage.com/nw/619.html