妊娠后期补饲硫酸镁钾盐对母猪生产性能、抗氧化能力及免疫功能的影响

【目的】研究妊娠后期补饲硫酸镁钾盐（Potassium magnesium sulfate，PMS）对母猪生产性能、血浆生化指标、抗氧化能力和免疫功能的影响。【方法】选取 3~4 胎次、健康状况良好且预产期相近的妊娠后期（妊娠85 d）史记长 × 大二元母猪 60 头，采用单因子试验设计，随机分为 4 组（每组 15 个重复，每个重复 1 头母猪），分别对每头母猪每天饲喂 PMS 0（CK）、5、10、15 g。母猪分娩后，停止补饲 PMS，泌乳期各组母猪自由采食相同的商业泌乳饲料，试验期至哺乳仔猪 18 日龄时结束。【结果】（1）补饲 PMS 对母猪产仔数、健仔数、背膘厚、产程、体重、泌乳期采食量、仔猪初生个体重、断奶仔猪数、哺乳期仔猪死亡数等指标均无显著影响；与对照组相比，补饲 PMS 后母猪妊娠后期的粪便评分呈线性增长（Plinear ＜ 0.05），且 10 g 补饲组显著提高（PANOVA ＜ 0.05）；补饲 PMS 的仔猪初生窝重、断奶仔猪窝重、哺乳期仔猪窝均增重和哺乳期仔猪日增重呈线性增加（Plinear ＜ 0.05），10 g 补饲组与对照相相比分别提高了 16.27%、24.42%、35.14% 和 31.64%；除了初生窝重外均有二次效应（PQuadratic ＜ 0.05），且组间差异显著（PANOVA ＜ 0.05）。（2）补饲 PMS 的母猪血浆中甘油三酯（TG）、胆固醇（CHO）、低密度脂蛋白（LDL）、胰岛素（INS）含量呈线性增加效果（Plinear ＜ 0.05），10 g 补饲组较对照组分别提高了50.00%、28.35%、25.00% 和 31.98%；TG 和 LDL 有二次效应（PQuadratic ＜ 0.05）。（3）补饲 PMS 的母猪血浆中免疫球蛋白 G（IgG）、免疫球蛋白 A（IgA）、免疫球蛋白 M（IgM）和谷胱甘肽过氧化酶（GSH-Px）含量呈线性变化（Plinear ＜ 0.05），10 g 补饲组较对照组分别提高了 17.10%、20.34%、8.00% 和 15.04%。（4）补饲 PMS 的母猪初乳中脂肪含量呈线性增加（Plinear ＜ 0.05），且显著提高（PANOVA ＜ 0.05），初乳中非脂乳固体、乳糖、蛋白质呈线性增加（Plinear ＜ 0.05）且有提高趋势（0.05 ＜ PANOVA ＜ 0.1），其中 10 g 补饲组的母猪初乳中脂肪较对照组提高了 51.42%。【结论】妊娠后期补饲 PMS 可显著改善母猪粪便评分，缓解母猪便秘，提高母猪的生产性能和机体健康，其中以 10 g 补饲效果最佳。

LI Qingqing, CHEN Jinhong, XIAO Biyang, ZHONG Weinan, LIN Xue, LIU Leilei, ZHANG Minyu（115）Effects of Supplemental Potassium Magnesium Sulfate on Performance, Antioxidant Capacity and Immune Function in Sows During Late Pregnancy

【Objective】The experiment was carried out to study the effects of potassium magnesium sulfate (PMS) on sow performance, plasma biochemical indicators, antioxidant capacity and immune function in late pregnancy. 【Method】By using simple factor design of the experiment, sixty sows (Landrace×Yorkshire) with 3-4 parity, good health and similar expected delivery in the third trimester of pregnancy (85th day of pregnancy) were randomly divided into 4 groups (15 replicates in each group and 1 sow in each replicate). The experimental groups during gestation were supplemented with PMS 0 (CK), 5, 10 and 15 g/d for each sow, respectively. After delivery, all sows during lactation were fed the same commercial lactation feed. The experiment ended on the 18th day of lactation.【Result】(1) Supplemental PMS had no significant effects on litter size, healthy litter size, back fat thickness, labor, body weight, feed intake in sows during lactation, and newborn weight of piglets, number of weaned piglets and number of deaths of lactating piglets. Compared with the control group, the fecal score of sows during late pregnancy after PMS supplementation showed a linear increase (Plinear ＜ 0.05) and 10 g/d group had significant effects (PANOVA ＜ 0.05); After supplementation with PMS, it showed a linear increase (Plinear ＜ 0.05) in newborn litter weight, litter weight of weaned piglets, average litter gain of lactating piglets and daily gain of lactating piglets (PANOVA ＜ 0.05). Compared with the control group, the newborn litter weight, litter weight of weaned piglets, average litter gain of lactating piglets and daily gain of lactating piglets in the 10 g/d group were increased by 16.27%, 24.42%, 35.14% and 31.64%. Except for newborn litter weight, all other indicators showed quadratic effect (PQuadratic ＜ 0.05) and significant differences were found between groups (PANOVA ＜ 0.05) ; (2) It showed a linear increase in the contents of triglyceride (TG), cholesterol (CHO), low-density lipoprotein (LDL) and insulin (INS) in plasma of sows supplemented with PMS (Plinear ＜ 0.05). The contents of TG, CHO, LDL and INS in the 10 g/d group increased by 50.00%, 28.35%, 25.00% and 31.98% compared with the control group; TG and LDL had a quadratic effect (PQuadratic ＜ 0.05). (3) Linear changes were found in contents of immunoglobulin G (IgG), immunoglobulin A (IgA), immunoglobulin M (IgM) and glutathione peroxidase (GSH-Px) (Plinear ＜ 0.05) in the plasma of sows after supplementation with PMS, and they were increased by 17.10%, 20.34%, 8.00% and 15.04% in the 10 g/d group, compared with the control group. (4) It showed a linear increase (PANOVA ＜ 0.05) in fat content of colostrum of sow with PMS supplementation (Plinear ＜ 0.05), with significant increase. Non-fat milk solids, lactose and protein were linearly increased (Plinear ＜ 0.05) and had an increasing trend (0.05 ＜ PANOVA ＜ 0.1). The fat content of colostrum supplemented with 10 g/d were increased by 51.42% compared with the control group. 【Conclusion】 PMS supplementation in late preganancy can significantly improve the fecal scores of sows, relieve sow constipation, and improve sow performance and body health, with 10 g/d supplementation as the optimal dose.