Cow infertility is one of the world's problems that plague the development of the dairy industry. The key to preventing non-infectious infertility is to make early diagnosis. However, it is difficult to determine whether a cow is pregnant with conventional examination methods, which brings great difficulties to the prevention of infertility in dairy cows. The use of cattle B-ultrasound linear array scanning method has the characteristics of fast, intuitive, accurate and non-destructive. It can accurately detect whether a cow is pregnant 28 days after mating, and has become an indispensable breeding equipment for cattle farms.

Cow infertility is one of the four major diseases that harm dairy cows in today's dairy production (hoof disease, mastitis, metabolic disease and infertility). Due to infertility, cows cannot reproduce normally, which prolongs the calving interval. Reproduction is an important link in the dairy industry. Reproduction work not only affects the number and quality of the herd, but also directly affects the milk production, milk quality, utilization value and economic benefits of the herd.

Balanced nutrition is the basis of cattle health and the guarantee of normal estrus, ovulation and conception of dairy cows. Cow infertility is largely related to nutrition. First of all, ensure the supply of daily rations to prevent low fertility due to negative energy balance. Secondly, we should avoid over-fat cows due to overnutrition or lack of exercise. Ensure protein supply and pay full attention to the supply of minerals and vitamins in the diet.

Infertility of dairy cows directly affects the calving interval of dairy farms, which is an important indicator of milk production and fertility of dairy cows and is closely related to the economic benefits of dairy farms. Internationally, many countries adopt a calving interval index of 365 days for dairy cows, while the calving interval days of most medium and small dairy farms in my country are much larger than this number, which seriously affects the economic benefits of dairy farms and restricts the development of my country's dairy industry.