There are no bulls in specialized dairy farms, and the annual mating season will be dedicated to bringing high-quality pure breed bulls to provide mating services. Dairy cows are also divided into bulls and cows. Cows are often kept for milk production. In addition to leaving a few strong and disease-free breeding cattle, the rest are treated as beef cattle.
Cows produce milk, milk makes milk powder. Bulls are used for mating, and dairy farm personnel should ensure that every cow is lactating, because only after fertilization does the cow produce milk. At present, dairy farms generally use artificial fertilization to promote dairy cows' milk production, so the status of male dairy is declining, mainly used to eat, such as milk steak.
The artificial insemination cost is very high, will it do any harm to cows?
As a result of technological progress, the dairy farms now basically use artificial fertilization to ensure the conception of cows. Artificial insemination of dairy cows will not cause any harm to cows.
How do cows undergo artificial insemination?
Cows can be inseminated with one or more of the following manifestations:
The estrus period is usually between the late estrus and the end of estrus. It is more appropriate to inseminate near the end of estrus symptoms in cows. The time for the ovum to maintain fertility in vivo is not more than 12 hours.
Therefore, within 12 hours after ovulation, the sperm should reach the fertilization site (oviduct ampulla). Ovulation of cows usually lasts for 3 to 15 hours after the end of oestrus symptoms, and the fastest time for sperm to reach the oviduct ampulla is only 2 to 15 minutes. Therefore, the nearer to the end of oestrus symptoms for artificial insemination, the higher the fertility rate of cows.
The insertion of the vas deferens into the deep part of the cervix is generally required at the insertion site, which is about 5-8 cm away from the cervix. However, there is no significant difference in the fertility rate among the deep part of the cervix, the uterine body or the corners of the uterus on the ovulation side.
At present, cows in dairy farms usually have estrus in the morning and have their first insemination from 4 to 5 p.m. and then decide whether to inseminate again the next morning according to the ovulation situation. If the cow estrus in the afternoon, the first insemination in the morning and the second insemination in the afternoon are considered according to the situation. Most dairy farms now inseminate only once.
Correct early diagnosis can reduce feed loss, determine the gestation period, calculate the expected delivery period and arrange the dry milk period. From 21 to 24 days after fertilization, the intact corpus luteum of 2.5 3 cm was touched, indicating that 90% of the women were likely to be pregnant. Two pregnancies were diagnosed 60 days after fertilization and 180-210 days after fertilization. The first was to confirm the fetus and the second was to ensure the fetus. Pregnancy 28 weeks, the fetus will grow stably.