Core Tip: This article introduces the vitamin supplementation of sow feed to improve the reproduction rate and resistance, for farmers to learn, see below for details.
The purpose of raising sows is to obtain more piglets, and there are two main indicators for measuring the reproductive performance of sows: the number of weaned pigs per sow per year and the years of sow breeding.
The factors affecting the reproductive performance of sows include genetics, nutrition, epidemics, environment and management. In recent years, with the rapid development of nutrition technology, research on improving the reproductive performance of sows through nutrient regulation has achieved initial success. The study found that almost all vitamins have a greater impact on the reproductive performance of breeding pigs. The main vitamins that affect the reproductive performance of sows are as follows:
1. Vitamin E: Vitamin E is closely related to reproductive function, can promote the production of thyrotropin (TH) and adrenocorticotropic hormone (ACTH) and gonadotropin, enhance ovarian function, increase follicles to increase luteal cells, and supplement the sow diet. Vitamin E not only can improve the conception rate, reduce fetal death, increase the litter size, but also enhance the anti-stress ability of piglets, reduce the death of piglets before weaning, shorten the weaning to estrus interval, and improve the quality of boar semen. Studies have shown that the number of litters and the number of litters in the sows fed high levels of vitamin E are higher, and the incidence of mastitis-uterine-milk-free syndrome (MMA) is lower. When the sow lacks vitamin E, the ovarian function declines, the sexual cycle is abnormal, it cannot be fertilized, the embryo is abnormally developed or the stillbirth occurs.
2. Folic acid: plays an important role in maintaining the reproductive performance of sows and promoting early fetal development. Its main function is the coenzyme in various enzyme systems, which is involved in the synthesis of sputum, so it is very important for the synthesis of DNA and RNA. In terms of maintaining the stable reproductive function of the sows, the number of litters can be increased; maintaining good lactation and preventing lactation disorders. Studies have shown (Lindemann et al., 1989) that the addition of folic acid to sow diets improves embryo survival and steadily increases litter size.
3. Beta-carotene: Supplementation of beta-carotene in sow feed will improve litter size, correct sow estrus and ovulation delay, and increase embryo survival. Beta-carotene is also associated with the synthesis of lutein, which is insufficient to cause termination of pregnancy. Recent studies have also found that the addition of beta-carotene to boar feed can promote testicular development and improve semen quality. Vitamin A and carotene are easily destroyed by oxidation, especially in the case of moist heat and contact with trace elements and rancid fat.
4. Vitamin A: Properly increasing the amount of vitamin A added to the diet can increase litter size and number of weaned piglets (Antipas, 2003). When the sow lacks vitamin A, the conception rate decreases, and the estrus is abnormal, dystocia, miscarriage, stillbirth, weak fetus, deformed fetus and placenta. Piglets blinking and limb paralysis are prone to pneumonia, diarrhea, etc.; young sows have delayed estrus, affect ovarian development, and have high embryo mortality.
5. Biotin: The main function is to maintain the health of the sow's hooves and prevent shins, lameness and sputum. At the same time, it can promote fetal growth and development, reduce fetal death and promote lactation, increase ovulation rate and conception rate of sows, and shorten the weaning to estrus interval. If the biotin content in the diet is less than 330ug, it will cause the stillbirth and the suckling pigs to grow and develop due to insufficient breast milk. The study found that supplementation with biotin can increase the length of the sow's uterine horn by 20%, which in turn increases the space occupied by the fetus in the uterus, which is of great significance for the growth and survival of the fetus.
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