發酵豆粕對肉豬免疫調節功能之影響

Abstract

本論文在探討發酵豆粕對免疫調節功能的影響，分別進行體內動物餵食模式和體外的細胞模式，體內試驗探討其對適應性免疫與先天性免疫的影響；體外試驗探討其對適應性免疫的影響。64隻豬隻平均飼養於16圍欄，分為兩組，一為飼糧中添加抗生素(對照組)，另一則用發酵豆粕取代抗生素(處理組)。兩組之間顆粒性白血球與單核球細胞產生活性氧能力或吞噬能力無顯著性差異，然而處理組可隨日齡增加並維持穩定產生活性氧與吞噬能力。適應性免疫反應結果顯示，處理組血漿中免疫球蛋白 G 含量高於對照組，亦有較好的T 細胞增生率，而細胞經刺激源作用後， TNF-α分泌比例與對照組相似，此結果顯示利用發酵豆粕取代抗生素可維持豬隻體內的先天性與適應性免疫反應，並可維持其原有的生長性能。細胞培養結果，低濃度(10 μg/ml)發酵豆粕蛋白質水萃物刺激豬隻 T 細胞分泌 IL-4 之能力顯著地高於未發酵豆粕者 (p < 0.05)，然而濃度間無顯著性差異，推測豆粕經發酵後產生之小分子蛋白質或胜肽，並非維持豬隻體內免疫力的主要成分。

The study aims to characterize the immunomodulating effects of fermented soybean meal. In vivo and in vitro studies were conducted in pigs and porcine T cells, respectively. The innate (non-specific) and adaptive (specific) immunity were investigated in vivo while in the cell-mediated immune responses were evaluated in vitro. A group of 64 pigs, evenly divided and raised in 16 pens, were separated into two groups: the control group and the experimental group. Pigs in the control group were fed with feed containing antibiotics while the experimental group consumed dietary supplements of fermented soybean meal. The oxidative burst and phagocytotic activities of the polymorphnuclear neutrophils and monocytes between the two groups showed no significant difference. However, reactive oxygen species (ROS) and phagocytotic activities were stably maintained in pigs fed with diets supplemented with fermented soybean meal. After LPS mitogen stimulation, monocytes of the two groups secreted equivalent levels of TNF-α.. When measuring adaptive immunity, both plasma IgG concentration and T-cell proliferation were higher in the experimental group than in the control group. These results showed that pigs supplemented with fermented soybean meal instead of antibiotics could maintain the innate and adaptive immunity, meanwhile, had the same performance between two groups. The effect of fermented soybean meal treatment to T cells was also evaluated in vitro. Comparing the effect of two treatments at low dosage, we found that porcine T cells secreted significantly higher (p < 0.05) levels of IL-4 when treated with fermented soybean meal than with unfermented soybean meal, however, not strictly correlated dose-dependently. We hypothesized that the proteins produced by fermenting soybean meal is not the major component in maintaining the immunity of pigs.