How should sows be raised to produce more piglets?

1. Select good gilts to keep. Gilts should be selected from the offspring of high-yielding boars and sows, and attention should also be paid to selecting those sows with many teats. 2. Appropriate age for first mating is very important. Generally, under normal feeding and management conditions, it is suitable for local-breed sows to begin mating at 6 to 7 months of age and a body weight of more than 50 kg, while for exotic breeds it is suitable to begin mating at 9 to 10 months of age and a body weight of more than 75 kg. Sows generally have the strongest reproductive capacity and produce the most piglets from the third to the seventh litter, and the piglets have a large birth weight, strong constitution and strong vitality. After the seventh litter, reproductive capacity gradually declines. After 6 to 7 years of use, the reproductive capacity of sows decreases significantly, and they should be replaced in time. Carefully observe sow estrus so as to mate at the right time. When the vulva of a sow in estrus has just begun to subside from redness and swelling, and the sow stands still when the waist is pressed by hand, it is the most suitable time for mating. In terms of time, the mating time is best 19 to 30 hours after the onset of estrus in the sow. This is because this period is close to the ovulation time of the sow. 3. Skillful feeding and management before mating. Before mating, sows should maintain a body condition of 70% to 80% fat, and feeding more green, succulent feed can promote normal estrus in sows, increase the quantity and quality of ovulation, help conception after mating, and increase the number of piglets born. Generally, the protein content should not be lower than 10% of the total feed; calcium should also be supplemented appropriately. The sow should be let out for exercise every day and exposed to sunlight to strengthen the constitution and promote ovulation. 4. Mating technique is also key. To increase the number of piglets born to sows, repeated mating and double mating are preferable. Repeated mating means that during one estrous period of a sow, one boar is used to mate twice in succession, with the interval between the two matings generally ranging from 12 to 20 hours, which can increase the number of piglets per litter by 0.5 to 1. Double mating means that during one estrous period of a sow, two boars of the same breed with distant blood relations or two boars of different breeds are used to mate with her. The method is that after the first boar mates with the sow, another boar is used to mate after an interval of 15 to 20 minutes, which can increase the number of piglets born to the sow by more than 15% to 20%. 5. Careful raising of pregnant sows ensures more births. In order to allow the fertilized eggs to develop fully in the sow's body, more feed rich in protein and vitamins should be fed in the early stage of pregnancy, appropriately matched with green feed, with a daily feed amount of 1.5 kg. At about 20 days of pregnancy, sows should be prevented from falling, fighting, being squeezed, and from sudden changes in feed and environment and from illness; after two months of pregnancy, they should be raised in separate pens, with appropriate exercise and sunlight, to prevent miscarriage; after more than three months of pregnancy, they enter the heavy pregnancy period, and the feed should be increased compared with the earlier stage, with a daily feed amount of 2.5 kg. When farrowing is approaching, the concentrate feed should be appropriately reduced to avoid mastitis and constipation and ensure that the piglets can be delivered smoothly.