The nutritional requirement for pregnant sows can be determined by the factorial method required for maintenance and production. According to the physiological changes of pregnant sows, the requirements for the nutritional needs of pregnant sows are less quantity, good quality, and nutritional balance in the early period; the quantity required in the later period is more, the quality is the best, and the nutrition is also balanced.
1. Energy needs
During pregnancy, excessively high and low energy levels have an effect on the reproductive performance of sows. In particular, excessive energy levels are harmful to sows. China's carcass-type pig raising standards indicate that the daily gain of pregnant sows is 300 to 5009. The standard stipulated 4 body weight levels (lower than gokg, 90 to 12 okg, 120 to 15 okg, and 15 okg or more) daily digestible energy requirement. Pre-pregnancy was 17.57 MJ, 19.92 MJ, 22.36 MJ, and 23.43 MJ, respectively. 23.43 MJ, 25.77 MJ, 28.12 MJ, 29.29 MJ.
2. Protein needs
China's meat fat type pig feeding standards stipulate that the pregnant sow's dietary protein content per kilogram is n% in the previous period and 12% in the latter period. Among them, lysine, methionine, threonine, and isoleucine were 0.35%, 0.19%, 0.28%, and 0.31% in the previous period, and 0.36%, 0.19%, 0.28%, and 0.31% in the later period.
3. Mineral needs
Calcium is involved in the synthesis of luteinizing progesterone and is also a mineral required for the maturation of oocytes. Lack of calcium in feed not only causes osteoporosis in sows, but can also lead to impeded fetal development and even death. Phosphorus deficiency in feed is also one of the causes of infertility and abortion in sows. The ratio of calcium to phosphorus is 1.5:l to 2:1. The U.S. NRC recommends a 0.4% salt requirement for pregnant sows. In addition, the trace elements manganese, iodine, selenium, zinc, copper, and chromium are also important for sow breeding.
4. Vitamin needs
When the mother's vitamin A is extremely low, the continued development of fertilized eggs is hindered. China's pig feeding standards stipulate that pregnant sows need 3200-3300IU per kilogram of dietary vitamin A, and NRC recommends 4000IU.
Vitamin D is very important for the metabolism of calcium and phosphorus and is essential vitamins for sow maintenance, pregnancy and lactation. China's pig raising standard is 160lu per kg of diet, and NRc is 200IU per kg of diet.
Vitamin E plays an important role in the body's anti-oxidation and immune function enhancement. Studies have shown that pregnant sows need 44-66 Iu/kg of vitamin E for maximum litter size. Above this level, the amount of vitamins in colostrum can be increased, thereby benefiting the health of piglets.
Rose Vibrator,Rose Vibrators Sex Toys,Sucking Rose Vibrator,Vibration Mode Rose Vibrators
Shenzhen Dongchen Hey E-commerce Co.,Ltd. , https://www.xxsexytoy.com