Fallopian tube jam 

Usually caused by salpingitis, it can be secondary to uterine inflammation or improper uterine flushing, resulting in the inability of sperm and egg to combine. When using bovine ultrasound to examine the fallopian tubes of cows, if there is blockage in the fallopian tubes, inflammatory substances can be seen blocking the fallopian tubes on the bovine ultrasound image.

Artificial insemination operation is unhygienic

Not strictly disinfecting or not disinfecting the cow's sperm gun, and not paying attention to hygiene during operation, can artificially cause uterine inflammation in normally estrus cows, resulting in repeated infertility. So in cows with endometritis seen on B-ultrasound, the follicles are normal, and after insemination, it is difficult to find the gestational sac using B-ultrasound examination. This type of problem is easily overlooked by artificial insemination workers and cattle breeders.

Regarding nutrition issues, nutrition

It has an impact on the normal development of the fetus and the normal pregnancy of cows, such as malnutrition or imbalance, which can cause miscarriage, infertility, delivery complications, as well as developmental disorders and diseases in calves. Therefore, nutritional issues have a significant impact. When malnourished, many malformed fetuses in cows can be detected on ultrasound.

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