本试验旨在探讨谷氨酰胺（GLN）对内毒素（LPS）刺激下中华鳖免疫功能和生产性能的影响。试验1：选择健康、均重为（332.35±13.75） g的中华鳖成鳖72只，随机分成4组（A～D组），每组设6个重复，每个重复3只。A、B组饲喂基础饲料，C、D组饲喂在基础饲料中添加2% GLN的饲料，并于试验第8天给予B、C组腹腔注射LPS 500 μg/kg BW。分别于注射后的第4、11和25天取样，检测T淋巴细胞转化率、血浆免疫球蛋白M(IgM)含量和溶菌酶（LSZ）活性以及肠黏液类分泌型免疫球蛋白A（SIgA）水平。试验2：选择健康、均重为（101.92±17.53） g的中华鳖幼鳖72只，随机分成4组（E～H组），每组设6个重复，每个重复3只。E、F组饲喂基础饲料，G、H组饲喂在基础饲料中添加2% GLN的饲料，并分别于第8天和第51天给予F、G组腹腔注射LPS 1 000 μg/kg BW。于试验第95天取样，检测各组鳖的肠道和肝脏组织结构、相对生长率、饲料系数、裙边比、体脂比以及肌肉的水分、粗脂肪、粗蛋白质和氨基酸含量。结果表明：与A组相比，B组血浆IgM的含量极显著升高（P4 d<0.01）；D组T淋巴细胞转化率极显著升高（P4 d<0.01，P11 d<0.01，P25 d<0.01），而B组T淋巴细胞转化率显著降低（P4 d<0.05，P11 d<0.05）。C组肠黏液类SIgA水平显著高于A、B组（P11 d<0.05，P25 d<0.05），D组肠黏液类SIgA水平极显著高于A、B组（P11 d<0.01，P25 d<0.01）。与E组相比，F组肝细胞萎缩变形，回肠绒毛萎缩(P<0.01)，G、H组回肠绒毛密度增大。此外，F组的相对生长率显著或极显著低于其余各组（PEF<0.05，PGF<0.05，PHF<0.01）；H组的相对生长率显著高于E、G组（P<0.05）；G、H组的体脂比显著低于E、F组（P<0.05）。由此得出，饲料中补充GLN能缓解LPS刺激下中华鳖血浆IgM含量的上升和细胞免疫功能的抑制，并对肠道类SIgA的分泌具有显著的促进作用；饲料中补充GLN能缓解LPS刺激下中华鳖生产性能的下降。

The experiment was conducted to study the effects of glutamine (GLN) on immune function and performance of lipopolysaccharide (LPS)-stimulated Pelodiscus sinensis. Seventy-two healthy adult Pelodiscus sinensis with an average weight of (33235±1375) g were randomly divided into 4 groups (groups A to D) with 6 replicates per group and 3 turtles per replicate in experiment 1. Turtles in groups A and B were fed with basal diet, and turtles in groups C and D were fed basal diet supplemented with 2% GLN and injected intraperitoneally with 500 μg/kg BW LPS on d 8 Samples were taken on d 4, 11 and 25 after the injection to detect the T lymphocyte transformation rate, plasma immunoglobulin M (IgM) content and lysozyme activity, and intestinal mucus secretory immunoglobulin A (SIgA)-like level. Seventy-two healthy juvenile Pelodiscus sinensis with an average weight of (101.92±17.53) g were randomly divided into 4 groups (groups E to H) with 6 replicates per group and 3 turtles per replicate in experiment 2. Turtles in groups E and F were fed with basal diet, and turtles in groups G and H were fed basal diet supplemented with 2% GLN and injected intraperitoneally with 1 000 μg/kg BW LPS on d 8 and 51. Organization structure of intestine and liver, relative growth rate, feed conversion ratio, body fat ratio, body skirt ratio, and the contents of moisture, crude protein, crude lipid and amino acids in muscle were determined on d 95. The results showed as follows: compared with group A, the plasma IgM content in group B was significantly increased (P4 d<0.01), and the T lymphocyte transformation rate in group D was significantly increased (P4 d<0.01, P11 d<0.01 and P25 d<0.01), while the T lymphocyte transformation rate in group B was significantly decreased (P4 d<0.05 and P11 d<0.05). The intestinal mucus SIgA-like level in group C was significantly higher than that in groups A and B (P11 d<005 and P25 d<0.05), and the intestinal mucus SIgA-like level in group D was significantly higher than that in groups A and B (P11 d<0.01 and P25 d<0.01). Compared with group E, the hepatocytes in group F were atrophic and deformed, the ileum-villus in group F was atrophic (P<0.01), and the density of ileum-villus in groups G and H was increased. In addition, the relative growth ratio in group F was significantly lower than that in other groups (PEF<0.05, PGF<0.05 and PHF<001); the relative growth rate in group H was significantly higher than that in groups E and G (P<0.05); the body fat ratio in groups G and H was significantly lower than that in groups E and F (P<0.05). It is concluded that GLN supplementation can inhibit the rise of plasma IgM level, relieve the inhibition of cellular immune function, and improve the SIgA-like secretion of intestinal canal of LPS-stimulated Pelodiscus sinensis. Besides, GLN supplementation can relieve the performance decline of Pelodiscus sinensis induced by LPS. ［Chinese Journal of Animal Nutrition，2011，23（4）：662 -669］