1, congenital genital dysplasia or deformity should be eliminated in time.
2. For the undernourished, protein, vitamins, minerals and other nutrients in the diet should be increased, and exercise should be strengthened.
3. Obese sows should lose weight, reduce feed or add roughage, and feed more green feed. Adding 3% calcium chloride to the feed can reduce weight for several days.
4. Inject sows with 500- 1000 units of chorionic gonadotropin or 200- 1000 units of pregnant horse serum, and lure them with boars, or use its synthetic product PG600 for better effect.
5. Ensure that sows have 4 hours of sunshine or artificial illumination every day, 16- 18 hours.
6. Let the sow that is not in estrus contact the sow that is in estrus.
7. Change the pigsty frequently and strengthen the stimulation.
8. Ensure that oestrus sows contact with boars every day 15 minutes, and change boars frequently.
9. Check whether there is too much zearalenone in the feed to avoid false pregnancy.
There are many factors that cause mating regression, which can be divided into periodic regression and irregular regression according to the time of regression. The reasons for regular estrus are abnormal physiological structure, seasonal infertility, cyst, operation and semen quality problems during artificial fertilization, excessive use of boars in this hybridization, long-term disuse or infertility of boars, and wrong breeding procedures. Irregular estrus is caused by fever, infectious diseases, environmental temperature, trauma and fighting, seasonal influence, overfeeding after mating and so on.
If my answer is useful to you, please choose "useful to me" or "beneficial". Thank you for adopting my answer.