How should the insemination method for cattle be correctly mastered?
The factors that determine the conception rate of cows include: the semen quality of the breeding bull, the estrus and ovulation function of the cow, the quality of artificial insemination technical operations, the insemination time, etc.
1. Semen quality: The quality of bull semen is mainly reflected in the strength of sperm motility. Sperm with strong motility can maintain fertilization capacity for a longer time, which is a prerequisite for promoting insemination and improving the conception rate. Therefore, the breed and individual quality of the breeding bull must be kept good, and the sperm motility of frozen semen used for insemination must not be lower than 0.3 after thawing.
2. Reproductive function: Whether the estrus and ovulation physiological function of the cow is normal affects the production of ova and the movement of released ova, fertilization, and the progress of embryonic development. If the cow has good body condition, is at a moderate age, and has normal and vigorous estrus, it is favorable for conception with frozen semen.
3. Insemination technique: Artificial insemination personnel must have a good command of artificial insemination techniques. Cleaning, disinfection, semen collection, semen processing, insemination, and other steps are closely linked, one after another. Failure to master any one step well may cause the adverse consequences of missed mating or infertility.
4. Insemination time: Only by choosing the most suitable time for insemination can sperm with strong vitality and ova meet at the fertilization site and improve the conception rate. If insemination is too early, the sperm lose fertilization capacity or die and cannot fertilize the ova; if insemination is too late, even if the sperm have strong fertilization capacity, the ova have been released for too long and have aged, so they also cannot be fertilized. The fertilization capacity of cows after ovulation is 20-24 hours, and the fertilization capacity of sperm in the cow reproductive tract is 28-50 hours. Generally, the conception rate of cows inseminated in the early estrus stage is low, and insemination 12 hours after estrus or 8 hours before ovulation is most suitable.
5. Identification of abnormal estrus: In production, some cattle experience silent estrus or estrus during pregnancy (false estrus), so rectal examination must be used to understand follicular development, master the patterns of estrus and ovulation, and carry out early pregnancy diagnosis to ensure conception and normal fetal development. Wang Shanqiang