In the cattle farm, the pregnancy check after the cows are mated mainly depends on the traditional rectal examination.Generally, it is carried out two months after breeding. The hand and arm are inserted into the rectum through the anus of the animal. The uterine horn, the middle uterus artery and the ovary are touched through the rectum. The feeling of the hand is used to judge pregnancy and pregnancy time. Low requirements, high accuracy.However, there are shortcomings in rectal examination: the operation technique is difficult to grasp, and the accuracy depends on the individual experience of the breeder; the shorter the pregnancy time, the greater the difficulty of judgment; the adverse consequences of infection and abortion; dirty and tired.
We judged the early pregnancy of the cows that 28 days after breeding by veterinary B-ultrasound, and the rate of empty pregnancy was 20%.After confirming with B type ultrasonic machine, follow-up observation ,and rectal examination of 60 days after breeding proved that B-ultrasound accuracy rate reached 96%, while traditional rectal examination can detect whether pregnancy or not at 45-60 days, and the accuracy rate is only 70% at the highest.Using veterinary B-ultrasound can observe the real-time images that development of uterus, embryo sac, and germinal vesicle in early pregnancy, intuitive perception, high accuracy, determine whether pregnancy or not at an early time, and reduce economic losses which was caused by empty pregnancy.