Feeding and management techniques of reserve sows

In pig production, sows must be constantly updated, that is, while eliminating slow estrus, old and weak, poor lactation ability and reproductive disorders, high-quality reserve sows should be selected in time for supplementary production. The so-called reserve sow refers to the sow that is reserved for breeding before the first mating. In the practice of raising pigs, the selection of reserve sows is very technical, which runs through the whole process of their growth and development, and should be comprehensively investigated according to the comprehensive performance and performance of their parents, siblings and themselves.

Fat control and boar induction

The reserve sows should be fully developed before 60kg, and should be properly restricted from 60kg to half a month before mating to prevent them from being overfed, feeding about 2kg a day, twice a day. The feed for growing and finishing pigs can be used for reserve sows.

When the reserve sow reaches 160 days old, it is best to drive the sow into the adult boar pen for 35 minutes every day. The external hormones secreted by the mandibular glands of adult boars help to induce estrus in young sows.

Short-term optimal feeding

The feeding of reserve sows can be strengthened and free feeding can be carried out 14 days before mating, so that sows can ovulate about 2.5 more eggs, which undoubtedly plays an important role in increasing the litter size of parturient sows.

Sows breed at least the second time of estrus

The number of ovulation in sows is related to the number of estrus. During first love, the litter size is low due to the low number of ovulation, and because the first-born sows account for about 30% of the total number of sows, how their litter performance directly affects the whole herd. The important purpose of inducing boars to estrus early is also to make them have several more estrus before mating. Some pig farms have no record of the number of estrus of their sows, which is undoubtedly an incorrect method of operation.

Single combination and double combination

The best time for mating should be 10-26 hours after the estrus sows are allowed to climb. Single mating means that in estrus in sows, boars are used to mate only once. Although this can reduce the number of boars, but because the optimal breeding time of sows is difficult to grasp, so single mating may reduce the conception rate and litter size.

Compounding refers to mating with the same boar once in 1 estrus, with an interval of 8 to 12 hours. In production practice, different boars of the same breed are often matched twice at intervals. This method can often have more dynamic sperm in the reproductive tract of sows, increase the chance of egg fertilization, and thus increase the litter size of sows.

Double mating means that two boars of the same breed or different breeds are mated with the same sow twice in a short time interval (10-15 minutes) during a period of estrus. This method can accelerate the maturation of eggs, shorten the time of ovulation and increase the number of ovulations. However, due to the short interval between the second mating, this method often has the same disadvantages as the monogamous mating.

With regard to the mastery of the best time for mating, there are four proverbs for reference: "if the vulva touches the grass, the insemination is just right; the expression is in a daze, and the semen is conceived; when you stand still, you are just right to mate; when the mucus thickens, it is the heat."