Li J, Li D F, Xing J J, Cheng Z B, Lai C H
National Feed Engineering Technology Research Center, State Key Laboratory on Animal Nutrition, China Agricultural University, Beijing, China.
J Anim Sci. 2006 Sep;84(9):2374-81. doi: 10.2527/jas.2004-541.
Three experiments were conducted to investigate the effects of beta-glucan supplementation on pig performance and immune function. In Exp. 1, 100 weaned pigs (8.65 +/- 0.42 kg of BW and 28 +/- 2 d of age) were used in a 35-d experiment to determine the effects of graded levels of beta-glucan. Pigs were randomly allotted to 1 of 5 treatments containing beta-glucan supplemented at 0, 25, 50, 100, or 200 ppm. Each treatment was replicated using 5 pens containing 4 pigs per pen. The ADG of pigs between d 14 to 28 and d 0 to 28 responded to dietary beta-glucan in a quadratic fashion (P < 0.05), whereas beta-glucan had no effect on ADFI and G:F in any period. In Exp. 2, 80 crossbred pigs (8.23 +/- 0.56 kg of BW and 28 +/- 2 d of age) were used in a 35-d experiment. Pigs were allotted to 1 of 2 dietary treatments (0 or 50 ppm of beta-glucan in the diet) using 10 pens with 4 pigs per pen. Pigs treated with beta-glucan had greater ADG in the 14- to 28-d (P = 0.05) and 0-to 28-d (P = 0.035) periods. The ADFI of pigs receiving beta-glucan was increased (P < 0.05) in the periods from 0 to 14, 0 to 28, and 28 to 35 d. The lymphocyte proliferation index in response to phytohemagglutinin (P = 0.051) and concanavalin A (P = 0.052) tended to decrease on d 14 in pigs supplemented with beta-glucan compared with pigs without supplementation. In Exp. 3, 24 barrows (8.89 +/- 0.20 kg of BW and 28 d of age) were used to investigate the immunological and somatotropic responses of pigs challenged with lipopolysaccharide (LPS). Experimental treatments were arranged in a 2 x 2 factorial, with the main effects of LPS challenge (saline vs. LPS) and dietary addition of beta-glucan (0 vs. 50 ppm). Pigs were raised individually in metabolic cages. Pigs were fed 0 or 50 ppm of beta-glucan for 28 d and then challenged with LPS (25 microg/kg of BW) or saline. After LPS injection, blood was obtained at 0, 1.5, 3, 4.5, 6, and 7.5 h to determine cytokine production and the somatotropic response. Dietary beta-glucan increased plasma interleukin-6 at 1.5, 3, and 4.5 h and tumor necrosis factor-alpha at 3 and 4.5 h and increased plasma interleukin-10 from 3 to 7.5 h after LPS challenge. The beta-glucan treatments had no effect on growth hormone. In conclusion, beta-glucan can selectively influence performance and partially offer benefits on somatotropic axis and immune function in weaned piglets challenged with LPS.
进行了三项试验以研究补充β-葡聚糖对猪生长性能和免疫功能的影响。在试验1中，选用100头断奶仔猪（体重8.65±0.42 kg，日龄28±2 d）进行为期35天的试验，以确定不同梯度水平β-葡聚糖的效果。仔猪被随机分配到5种处理中的一种，日粮中β-葡聚糖添加量分别为0、25、50、100或200 ppm。每个处理重复5次，每个栏舍饲养4头猪。14至28日龄以及0至28日龄仔猪的平均日增重（ADG）对日粮中β-葡聚糖呈二次曲线反应（P<0.05），而β-葡聚糖在任何阶段对平均日采食量（ADFI）和料重比（G:F）均无影响。在试验2中，选用80头杂交仔猪（体重8.23±0.56 kg，日龄28±2 d）进行为期35天的试验。仔猪被分配到2种日粮处理中的一种（日粮中β-葡聚糖含量为0或50 ppm），共10个栏舍，每个栏舍饲养4头猪。在14至28日龄（P=0.05）和0至28日龄（P=0.035）阶段，添加β-葡聚糖的仔猪ADG更高。在0至14日龄、0至28日龄以及28至35日龄阶段，添加β-葡聚糖的仔猪ADFI增加（P<0.05）。与未添加β-葡聚糖的仔猪相比，在14日龄时，添加β-葡聚糖的仔猪对植物血凝素（P=0.051）和刀豆蛋白A（P=0.052）的淋巴细胞增殖指数有降低趋势。在试验3中，选用24头公猪（体重8.89±0.20 kg，日龄28 d）来研究脂多糖（LPS）攻毒仔猪的免疫和生长激素反应。试验处理采用2×2析因设计，主要因素为LPS攻毒（生理盐水与LPS）和日粮添加β-葡聚糖（0与50 ppm）。仔猪单独饲养于代谢笼中。仔猪饲喂含0或50 ppmβ-葡聚糖的日粮28天，然后用LPS（25 μg/kg体重）或生理盐水攻毒。LPS注射后，在0、1.5、3、4.5、6和7.5小时采集血液，以测定细胞因子产生和生长激素反应。日粮中β-葡聚糖可使LPS攻毒后1.5、3和4.5小时血浆白细胞介素-6增加，3和4.5小时肿瘤坏死因子-α增加，3至7.5小时血浆白细胞介素-10增加。β-葡聚糖处理对生长激素无影响。总之，β-葡聚糖可选择性地影响生长性能，并对LPS攻毒的断奶仔猪生长激素轴和免疫功能有部分益处。
