Changes in the physiological characteristics and production performance of modern sows, such as changes in the proportion of lean meat and fat in the body composition, greater maturity, higher litter size, higher survival rate of piglets, more milk production, and feed intake potential Decline, nutrition needs individual differences, the "joint" effect between different parity is stronger, and it is more sensitive to nutrition, environment and management "stress factors", which makes the pig farm production practice pay more and more attention to the sow. Stage nutrition and feed amount. The differentiation of sows and lyrics is increasingly demanding for nutrition. The management objectives and feed quantities at different stages are generally based on the following feeding methods.

However, sows such as heat stress in high temperature environment in summer, high energy needs in winter and cold conditions, feed intake during abnormal conditions such as litter, weaning and estrus breeding are often insufficient, so that The lack of nutrition affects the normal reproductive performance of sows.

In production, we often have sows with late estrus (especially the second birth of the second birth), difficult breeding, insufficient milk in the sow, and fewer birth defects. In addition to pathological reasons, the root cause lies in nutrient intake ( On the one hand, the lack of nutrient intake and nutritional imbalance, on the other hand, the toxicity of the feed mycotoxins destroys immunity and reproductive performance) and is related to the large consumption of nutrients for fetuses and lactation. The figure below shows the loss of five mineral elements in sows after weaning in the second place: in fact, the loss of nutrients such as other undetected mineral elements, vitamins, amino acids and the like also makes the sows negative in nutrition. Balanced state, under this physiological condition, the sow first restores its own nutritional status after weaning, thus prolonging the interval between the next estrus and ovulation.

The preparation of sow feed should be based on the physiological characteristics of the sow production cycle, such as fetal growth and maternal weight gain during gestation. The catabolism dominated by lactation for the growth of sows in lactating pigs is strong; after weaning The ovulation mating mother is mainly based on the anabolism of the recovery energy. For example, the preparation of the gilt feed should enable the gilts to achieve the following breeding objectives: the weight of the breeding is 130-140 kg (220-230 days), and the thickness of the P2 point is 膘. 18-20 mm. To this end, the nutritional level of the sows before and after breeding is given.

Short-term superior feeding of sows: Free feeding for about 2 weeks before breeding, can increase the number of ovulation. Generally, the third estrus and backing 17-20 mm are suitable for breeding. After breeding, the sow feed intake should be controlled, because excessive energy intake will greatly reduce the implantation of fertilized eggs, which will affect the litter size. . However, in terms of the limited feeding amount at this stage, controlling the feed intake of the compound feed to limit the energy intake also limits the intake of nutrients such as amino acids, vitamins and mineral elements, but at this time the sow completes the egg. The mother needs more nutrients for a series of pregnancy activities, such as fertilization, implantation of fertilized eggs, rapid division of fertilized eggs, and physiological changes in endometrial histology. Therefore, the contradiction between the control of energy and the strengthening of nutrients such as amino acids, vitamins and mineral elements is formed, and the daily pregnancy or breastfeeding materials cannot balance the nutritional needs of the first 3 weeks of pregnancy. Therefore, this stage should use a special premix and a reasonable energy-protein ratio scientific formula to meet the higher requirements of nutrients such as amino acids, vitamins and mineral elements in the pre-pregnancy period while controlling the excessive intake of energy.

In the scale of the daily visits, the author found that the farmer saw the materials and the phased materials in the same period, but most of them ignored the special requirements of the core premix after weaning to 3 weeks after breeding, and the high temperature season. Feed intake is not up to standard. In small-scale pig farms in professional households, it is wrong to think that the sensation is moderate, which means that the sows are more healthy. Therefore, once the estrus is not timely or the infertility is considered as a pathological factor after weaning, it is rash to use drugs, especially aphrodisiacs, to aphrodisiac, but often the effect There are very few births that are not good. In fact, in many cases, it is related to micronutrient related to ovulation and fertilization and implantation.

In summary, especially in the summer, the nutritional status of breeding pigs has a more obvious impact on reproductive performance. Pay attention to the following points in actual production:

First, pay attention to summer cooling, winter insulation;

The second is to select the special premix for the pigs according to the physiological cycle of the breeding pigs to prepare special feeds for each stage, and strictly control the quality of the raw materials;

The third is to look at the feed, and formulate feeding standards according to individual differences, parity and physiological cycle;

Fourth, the sow feeding the wet mix can increase feed intake and feed utilization. Feeding sows in high temperature for more than 3 meals a day;

The fifth is to pay attention to the detoxification of mycotoxins in the feed.

Cooperate with the diagnosis of early pregnancy of sows, establish breeding records of breeding pigs, and adjust the sow herd in time.