1, before the rough after the fine feeding. For breeding sows that have a particularly good sensation before breeding, this feeding method can be used. Because the fetus is very small in the first trimester of pregnancy, the sow itself is lyrical, neither need to increase nutrition again, generally can be reared according to the nutritional level before mating, that is, feed more excellent green juicy feed, feed less or not feed concentrate. By the end of pregnancy, the growth and development of the fetus will increase rapidly, requiring a lot of nutrition, especially minerals, proteins, and vitamins. It is necessary to appropriately increase the concentrate to meet the requirements for the growth and development of the fetus and the lactation of the sow after delivery. 2. Step-by-step feeding methods. Suitable for sows who are primiparous or lactating, because the primiparous sow itself is in the stage of growth and development, and the sows that are bred during lactation are responsible for the dual tasks of lactation and pregnancy, which require the most nutrition, in addition to guaranteeing the fetus. In addition to the normal development of good nutrition, sow needs to maintain and lactate itself. Therefore, in the early stages of pregnancy, mainly green and rough feeds are used. With the increase in the date of pregnancy, the proportion of concentrates is gradually increased. At the same time, attention is paid to the supply of protein and minerals, reaching the highest level of nutrition in the first half of the month of delivery. Jiangsu Tiera Biotechnology Co., Ltd , https://www.tierabio.com