Imported cows with uterine involution after delivery are monitored using ultrasound. After giving birth, it takes about 20-31 days for the uterus of a cow to return to normal. In fact, the degree and time of uterine involution depend on various factors such as breed, nutrition, parity and fat condition, season, and environment. The continuous rectal exploration method using imported cattle was used to monitor the recovery time of the gestational angle, empty angle, and cervix of postpartum Holstein cows, which were approximately 27 days, 31 days, and 37 days, respectively.

Due to the thick and dense structure of the cervical wall, ultrasound images show strong echoes. The folds formed by the mucosa inside the wall also show strong echoes in imported cattle ultrasound images, but are weaker compared to the uterine wall. The uterine wall is also a dense tissue structure, which appears as a strong echo in imported cattle ultrasound images. When the uterine body is not open, the junction of the upper and lower walls appears as a strong echo in ultrasound images. And it also determines reproductive indicators such as postpartum estrus time, mating rate, conception rate during estrus, and number of empty days for cows.

Imported cattle can also be diagnosed with endometritis, uterine inflammation, uterine abscess, uterine effusion, fetal mummification, etc. using B-ultrasound. Endometritis is a common disease of the reproductive organs in cows, which can easily cause infertility and seriously affect the reproduction of cattle herds. When cows suffer from endometritis, ultrasound examination shows intact uterine contours, but endometrial hyperplasia with intermittent or continuous light spots or strong echo spots.

When using imported cows for ultrasound examination of infertile cows, it was found that the uterine wall contour of cows with endometritis was clear, the inner edge was irregular, and the uterine wall was thickened. Uterine inflammation usually has inflammatory exudate, and generally does not produce hypoechoic or cloudy echoes; Uterine abscess is commonly seen in clinical practice, with purulent discharge from the external genitalia and adhesions to the tail. In severe cases, the contents can be thick and thick. Ultrasound examination shows that the outline of the uterine cavity is blurred, the cavity is dilated, and there is a large snowflake shaped echo inside the cavity. Uterine effusion usually shows watery mucus flowing out of the vulva, and imported cows can be seen with a large amount of echogenicity in the uterus by B-ultrasound. The fetal mummification results in the death of the fetus in the abdomen, with the absorption of water from the fetus's body, leading to mummification. Ultrasound shows block shaped echoes with strong echoes in the uterine horn.