Would you please have the techniques of sow feeding and management at different stages?

(agricultural get Rich Network) would you please have the techniques for raising and managing sows at different stages? -- 1 the breeding of reserve sows (3 months old-first breeding) in order to make the sows have a good and stable reproductive performance, the feeding of reserve sows is very important. A scientific and reasonable feeding scheme should make the body weight of reserve sows reach 130,140 kg,P2 and the fat thickness of 18,20 mm at the age of 220 ~ 240 days. There were two normal estrus, thus mating in the third estrus. In order to achieve this goal, it is suggested that the following feeding scheme should be adopted: 45-75 kg body weight stage to feed growing pigs and feed freely. The sows were fed with diets during the growing period of 75 to 100 kg, and the feeding was restricted appropriately. The nutrition level of special diet for young sows is different from that of pregnant and lactating sows, which contains appropriate levels of calcium, phosphorus, amino acids, biotin, folic acid and so on, which plays an extremely important role in the development of bone and reproductive system of young sows. it is helpful to improve the reproductive performance of the first fetus and prolong the reproductive and utilization life of sows. Two weeks before 100 kg- breeding, continue to feed the special diet of sows, limit the daily feeding amount to 2.5-3.0 kg, prevent the reserve sows from being overfat, the hormone secretion of obese sows is out of balance, and there will be more fat accumulation in the ovaries, which will affect the estrus and ovulation number of reserve sows. Estrus supplementary feeding during the preparation period of mating (2 weeks before mating) can increase the number of ovulation of reserve sows. That is to say, increasing the dietary energy concentration or daily feeding amount 10-14 days before mating is helpful to the secretion of estrogen and follicle stimulating hormone, thus increasing the number of ovulation. It is suggested that the daily feeding amount at this stage should be 3.0-3.5 kg or free feeding. The goal of feeding sows during pregnancy is to produce a litter of piglets with large number, birth weight, uniformity and strong vitality, while sows are healthy and have fully developed mammary glands and good body nutrient reserves. From the combination of sperm and egg, embryo implantation, fetal development to delivery, this period is called pregnancy for sows and embryonic stage for newly formed individuals. In order to achieve the feeding goal of pregnant sows, reasonable feeding should be carried out according to the law of embryo growth and development, breast development and nutrient reserve of sows. It is suggested that the pregnancy period should be divided into early pregnancy, second trimester and late pregnancy. Accurately control the body weight gain of sows and ensure the growth and development of fetuses, which can not only save production costs, but also do not affect the realization of the highest reproductive efficiency of sows. (2) feeding of sows in the first trimester of pregnancy (28 days after mating) the goal of sows in the early stage of pregnancy is to reduce the death of embryos. It takes about 11 to 12 days for the fertilized egg to move to the uterine horn, and then the embryo begins to be implanted and ends on the 24th day. If the embryo cannot be implanted, the embryo will die, resulting in a low embryo survival rate and a decrease in litter size. Early pregnancy is the first peak of embryonic death. the main reason is that the nutrient concentration of sows is too high, which will reduce the secretion of progesterone, so the feed intake of sows should be controlled in the early stage of pregnancy. so that their intake of nutrients can meet their own needs (including the needs of the growth and development of young sows). Therefore, once the sows are mated, the pregnant sow feed should be used immediately, and the daily feed amount should be controlled at 1.6 / 2.0 kg. (3) feeding of sows in the second trimester of pregnancy the goal of raising sows in the second trimester of pregnancy is to ensure the needs of fetal development and self-metabolism of sows (including the needs of growth and development of young sows). Under normal circumstances, the feeding amount at this stage should be controlled at 2.3-2.8 kg. On this basis, the feeding amount of thin sows should be increased appropriately to ensure that the body condition of sows return to the ideal condition during this period. However, sows in poor health should not be overfed, because overfeeding at this stage will lead to a reduction in free feed intake during lactation. For sows in poor health after weaning, it is recommended to increase the amount of feed after weaning, or even feed freely, and postpone the breeding period of estrus. The weight gain of newborn sows during pregnancy is about 10% more than that of parturient sows, so the feeding amount of parturient sows should be about 10% higher than that of parturient sows under the same body condition. After 75 days of pregnancy is the critical period of breast development, excessive energy intake will increase the fat deposition in the breast and reduce the number of secretory cells in the breast, resulting in a decrease in lactation during lactation. -4 feeding of sows in the third trimester of pregnancy (84-112 days of pregnancy) feeding of sows in the third trimester of pregnancy is very important to the growth and development of the fetus, during which the fetus grows very rapidly. 60% and 70% of the birth weight of piglets comes from the rapid growth of one month before birth. This stage is also the period of full development of mammary gland. in order to ensure the rapid growth of fetus and the development of mammary gland of sows, it is recommended that the daily feeding amount is 2.8~3.5kg. Feeding of sows during the perinatal period (3 days before delivery-7 days after delivery) the goal of raising sows in the perinatal period is to make the sows give birth smoothly, reduce the occurrence of constipation and ensure the recovery of postpartum appetite of sows. The diet began to be reduced gradually on the 3rd day before delivery, and the daily reduction was 0.5-1.0 kg. In general, sows are not fed on the day of parturition. If sows are fed, they should be fed 1.5-2.0 kg feed. Sows were fed with lactation sow feed from postpartum period, and the feeding amount was increased by 0.5 ~ 1.0 kg per day, and the sows were fed freely at 7 days after delivery. In the early postpartum period, due to feeding restrictions, sows are prone to constipation. In order to prevent constipation, fiber or laxative feed can be properly added to the diet, such as wheat bran and beet dregs, and it is also a better way to add chemical laxatives such as magnesium sulfate and potassium sulfate. at the same time, adequate drinking water for sows must be ensured. In addition to ensuring the drinking water of sows, the physical exertion during childbirth and postpartum sleepiness make the sows like to lie down, and the breeders should regularly pat the sows to promote their drinking water. Feeding sows during the peak lactation period (7 days postpartum-weaning) the goal of sows feeding during the peak lactation period is to maximize the milk yield of sows and at the same time control the weight loss of sows so as to ensure that the sows are in proper condition after weaning and enter the next reproductive cycle smoothly. Modern sows need to have a high feed intake during the peak lactation period because of their large body weight, large litter size and high lactation, but the appetite of modern sows is often poor, so they need to be fed a high-energy and high-protein diet with a balance of energy and protein. and through the use of wet mixing, increasing feeding times (4 times a day) and other measures to increase feed intake of sows. The nutritional intake of lactating sows is related to their body weight, milk yield, number of piglets, growth rate of piglets and temperature of lactation house, etc. if the nutrition intake of sows is insufficient (negative nutritional balance), sows will use amino acids and fat from their body tissues to synthesize milk, especially in high-yielding lactating sows, which will cause greater tissue loss and hormone imbalance in sows on the one hand. As a result, the interval between weaning and reestrus is prolonged, the litter size of the next baby is reduced, and the long-term negative nutritional balance will also lead to the decrease of the average litter size and the shortening of reproductive utilization years. On the other hand, the use of fat from body tissue to synthesize milk will increase the long-chain fatty acids in the milk, which in turn leads to diarrhea in piglets due to indigestion. The situation of negative nutritional balance can be improved by increasing feed intake or increasing dietary nutrition level. During the peak lactation period, due to the need of metabolism and synthetic milk, the daily drinking water of sows is up to 20,30L, so adequate drinking water for sows must be ensured, otherwise the feed intake and lactation will be affected. -7 breeding of sows during the empty breeding period (weaning-re-breeding) the feeding goal of sows in the empty breeding period is to breed in estrus 5-7 days after weaning. Sows continue to feed nutritious lactation sows after weaning. Sows may not be fed on the day of weaning due to weaning stress, but if sows are fed, it is not necessary to reduce sows' feed intake, but should increase sows' feed intake as soon as possible. The daily feeding amount during the whole breeding period is 3.0-4.0 kg or free feeding, which is beneficial to the recovery of sows' body condition, promote the development of follicles, contribute to the secretion of estrogen and follicle-stimulating hormone, and finally benefit the estrus, ovulation and conception of sows.