本试验旨在研究猪胎盘粉对哺乳母猪繁殖性能、血清免疫和生殖激素指标及乳成分的影响。选取36头预产期、体重、胎次相近的经产大×长二元母猪，随机分为4个组，每组9个重复，每个重复1头猪。对照组饲喂基础饲粮，试验Ⅰ、Ⅱ、Ⅲ组分别在基础饲粮中添加1%、3%、5%的猪胎盘粉。试验于妊娠104 d开始，至产后21 d结束。结果表明：1）试验Ⅲ组泌乳力、仔猪断奶个体均重和仔猪断奶窝重均极显著高于对照组（P<0.01），试验Ⅱ、Ⅲ组仔猪平均日增重显著或极显著高于对照组（P<0.05或P<0.01），试验Ⅲ组母猪体重损失显著低于对照组（P<0.05）。2）母猪分娩后第3天，试验Ⅱ组血清白细胞介素-6（IL-6）含量显著或极显著高于对照组和试验Ⅰ、Ⅲ组（P<0.05或P<0.01），试验Ⅰ、Ⅱ、Ⅲ组血清免疫球蛋白A（IgA）含量显著高于对照组（P<0.05），试验Ⅰ组血清免疫球蛋白M（IgM）含量极显著高于对照组、试验Ⅲ组（P<0.01），试验Ⅱ、Ⅲ组血清催乳素（PRL）含量显著高于对照组（P<0.05）。母猪分娩后第15天，试验Ⅰ、Ⅱ组血清IgA含量显著或极显著高于对照组和试验Ⅲ组（P<0.05或P<0.01），试验Ⅱ组血清免疫球蛋白G（IgG）含量显著或极显著高于对照组和试验Ⅲ组（P<0.05或P<0.01）；试验Ⅰ组血清IgM含量极显著高于对照组（P<0.01）。试验Ⅰ、Ⅱ、Ⅲ组血清PRL含量极显著高于对照组（P<0.01）。3）试验Ⅲ组乳脂率显著高于对照组和试验Ⅰ组（P<0.05），试验Ⅱ、Ⅲ组乳糖率显著或极显著高于对照组和试验Ⅰ组（P<0.05或P<0.01）。由此可见，饲粮中添加猪胎盘粉能改善哺乳母猪繁殖性能、血清免疫和生殖激素指标及乳品质。在本试验条件下，猪胎盘粉的适宜添加量为3%。

This experiment was conducted to study the effects of pig placental powder on reproductive performance, serum immune and reproductive hormone indexes and milk composition of lactating sows. Thirty-six multiparity sows (Large White×Landrace) with similar weight and parity were randomly into 4 groups with 9 replicates per group and 1 sow per replicate. Sows in the control group was fed a basal diet, and others in experimental groups (groups Ⅰ, Ⅱ, and Ⅲ) were fed the basal diets supplemented with 1%, 3%, and 5% pig placental powder, respectively. The trial began on 104 days after pregnancy and ended on 21 days after delivery. The results showed as follows:1) the milk ability, weaning piglet average weight and litter weaning weight in group Ⅲ were significantly higher than those in the control group (P<0.05), the average daily gain of piglets in groups Ⅱ and Ⅲ was significantly higher than that in the control group (P<0.05 or P<0.01), the weight loss of sows in group Ⅲ was significantly lower than that in the control group (P<0.05). 2) On the 3rd day after delivery, the serum interleukin-6 (IL-6) content in group Ⅱ was significantly higher than that in control group and groups Ⅰ and Ⅲ (P<0.05 or P<0.01), the serum immunoglobulin A (IgA) content in groups Ⅰ, Ⅱ and Ⅲ was significantly higher than that in the control group (P<0.05), the serum immunoglobulin M (IgM) content in group Ⅰ was significantly higher than that in control group and group Ⅲ (P<0.01), the serum prolactin (PRL) content in groups Ⅱ and Ⅲ was significantly higher than that in the control group (P<0.05). On the 15th day after delivery, the serum IgA content in groups Ⅰ and Ⅱ was significantly higher than that in the control group and group Ⅲ (P<0.05 or P<0.01), the serum immunoglobulin G (IgG) content in group Ⅱ was significantly higher than that in the control group and group Ⅲ (P<0.05 or P<0.01), the serum IgM content in group Ⅰ was significantly higher than that in control group (P<0.01), the serum PRL content in groups Ⅰ, Ⅱ and Ⅲ was significantly higher than that in control group (P<0.01). 3) The milk fat ratio in group Ⅲ was significantly higher than that in control group and group Ⅰ (P<0.05), the lactose ratio in groups Ⅱ and Ⅲ was significantly higher than that in control group and group Ⅰ (P<0.05 or P<0.01). It is suggested that adding pig placental powder into the diet can improve reproductive performance, serum immune and reproductive hormones indexes and milk quality of lactating sows. The appropriate amount of pig placental powder is 3% in this experimental condition.