【作者】 张艳艳；

【导师】 李福昌；

【作者基本信息】 山东农业大学 ， 动物营养与饲料科学， 2010， 硕士

【摘要】 本试验研究了日粮不同硒水平对断奶～3月龄生长肉兔生长性能、抗氧化指标、血液生化指标、血清激素、组织硒沉积、肉品品质以及GSH-Px1 mRNA表达量的影响。试验分断奶～2月龄,2～3月龄两个阶段,选用断奶肉兔120只,随机分为5组,每组的试验兔体重相近、公母各半,5组试验兔的日粮硒添加水平依次为:0、0.15、0.30、0.45、0.60 mg/kg。研究结果如下:日粮中不同的硒添加水平对断奶～2月龄的日采食量没有显著影响(P=0.3966)。平均日增重(ADG)、料重比(F/G)受日粮硒水平影响显著(P=0.0294,P=0.0156),日粮中添加硒可显著改善肉兔平均日增重(ADG)和料重比(F/G)。日粮添加不同水平硒对肝脏硒沉积影响极显著(P<0.0001),随硒添加水平的增加硒沉积极显著增加,当硒添加量达到0.45 mg/kg时,硒的沉积量达到最大值。日粮硒水平对肝脏、血清谷胱甘肽过氧化物酶活性(GSH-Px)影响显著(P<0.0001,P=0.0281),对肝脏、血清超氧化物歧化酶(SOD)没有显著影响(P=0.1319,P=0.8848),对肝脏、血清总抗氧化能力(T-AOC)影响显著(P=0.0406,P=0.0414),对肝脏、血清过氧化氢酶(CAT)影响显著(P=0.0209,P=0.0186),0添加组肝脏丙二醛(MDA)含量极显著高于添加组(P=0.0018)。日粮硒水平对血清总蛋白(TP)没有显著影响(P=0.2401);对血清总胆固醇(TC)和甘油三酯(TR)影响显著(P=0.0349,P=0.0001),未添加组总胆固醇(TC)和甘油三酯(TR)含量显著或极显著高于各添加组(P<0.05或P<0.01)。日粮中高水平的硒(0.45、0.60mg/kg)可以极显著的提高高密度脂蛋白(HDL)在血清中的含量(P=0.0077),但HDL在两高水平添加量之间没有显著差异(P>0.05),0、0.15、0.30 mg/kg组之间没有显著差异(P>0.05)。日粮硒水平对低密度脂蛋白(LDL)影响极显著(P=0.0055),未添加组显著高于添加组(P<0.05)。日粮硒水平对肝脏GSH-Px1 mRNA表达量的影响极显著(P<0.0001),0.15mg/kg组极显著高于未添加组和其他各添加组(P<0.01),0和0.30 mg/kg组极显著高于0.45和0.60mg/kg组(P<0.01)。综合本试验指标,当基础日粮硒含量为0.08 mg/kg时,断奶～2月龄肉兔日粮中硒的适宜添加量为0.15 mg/kg。日粮硒添加水平对2～3月龄肉兔日采食量(ADI)没有显著影响(P=0.1202),对平均日增重(ADG)和料重比(F/G)影响显著(P=0.0194,P=0.0401),0.15和0.30 mg/kg添加组显著优于未添加组(P<0.05)。日粮硒水平对肝脏、血清和肌肉谷胱甘肽过氧化物酶(GSH-Px)影响显著或极显著(P=0.0114,P=0.0009,P<0.0001),对肝脏和血清超氧化物歧化酶(SOD)影响显著(P=0.0323,P=0.0149),对肝脏过氧化氢酶(CAT)影响显著(P=0.0434),0.30 mg/kg添加组显著高于未添加组(P<0.05),对肝脏和肌肉丙二醛(MDA)浓度影响显著(P=0.029,P=0.0190),对血清总抗氧化能力(T-AOC)影响显著(P=0.0376)。日粮硒水平对肌肉失水率影响显著(P=0.0325),0.15 mg/kg添加组显著优于0和0.6 mg/kg添加组(P<0.05),对肌肉滴水损失影响显著(P=0.0042),未添加组显著高于添加组(P<0.05)。肌肉PH(45 min,24 h)受日粮硒水平影响不显著(P=0.4734,P=0.3051)。日粮中添加硒可以显著降低肌肉剪切力(P=0.0285),极显著提高肌肉、肝脏中的硒浓度(P=0.0054,P=0.0005),随硒添加水平的增加硒沉积极显著增加,当硒添加量达到0.30 mg/kg时,硒的沉积量达到最大值。日粮硒水平显著提高血清总蛋白水平(TP)(P=0.0338),对血清甘油三酯含量没有显著影响(P=0.0895),日粮中添加硒可以显著降低血清中胆固醇(TC)(P=0.0497)和低密度脂蛋白的含量(LDL)(P=0.0386),提高高密度脂蛋白的含量(HDL)(P=0.0235)。日粮硒水平对血清促甲状腺激素(TSH)影响不显著(P=0.0895);日粮中添加硒可以降低血清中四碘甲腺原氨酸(T4)的水平(P=0.0327),并且升高甲状腺激素(T3)的水平(P=0.0107)。日粮硒水平对2～3月龄肉兔肝脏GSH-Px1 mRNA表达量的影响极显著(P<0.01),0.15 mg/kg组极显著高于未添加和其他添加组。综合本试验指标,当基础日粮硒含量为0.08 mg/kg时,2～3月龄肉兔日粮中硒的适宜添加量为0.15 mg/kg。更多还原

【Abstract】 The experiment was designed to study the effect of dietary different selenium supplement levels on production performance, antioxidant indices, meat quality blood metabolites, serum hormone concentration and liver GPX mRNA expression of weaned to 3 months old meat rabbits. One hundred and twenty weaned growing meat rabbits were allocated to individual cages and randomly divided into five groups. Animals in each group were fed with a diet with the following selenium additional levels: 0, 0.15, 0.30, 0.45 and 0.60 mg/kg selenium in original matter basis respectively. The results were as follows.Dietary selenium levels significantly affected average daily gain (ADG) and feed/gain (P=0.0294, P=0.0156), however, selenium supplementation had no influence on average daily intake (ADFI) (P=0.3966). Selenium supplementation had significant influence on liver selenium concentration (P<0.0001), with the highest concentration in 0.45 mg/kg group. Dietary selenium supplementation significantly affected liver and serum GPX (P<0.0001, P=0.0281), but had no influence on their superoxide dismutase (SOD) (P=0.1319, P=0.8848). Liver and serum total antioxidant capacity (T-AOC) and catalase (CAT) (P=0.0406, P=0.0414) was significantly affected by dietary selenium supplementation. Liver malondialdehyde (MDA) (P=0.0018) tend to be higher in control group than in selenium supplementation groups. There was no significant difference on serum total protein (TP) (P=0.2401). Selenium supplementation can reduce serum total cholesterol (TC) (P=0.0349), triglyeride (TRI) (P=0.0001) and low density lipoprotein (LDL-C) concentration (P=0.0055), and at the same time increase the concentration of high density lipoprotein (HDL-C) (P=0.0077). Selenium supplementation significantly affect liver GPX m RNA expression (P<0.0001). In conclusion, the appropriate dietary selenium supplement level of weaned to 2 month-old meat rabbits was 0.15 mg/kg (The concentration of selenium in basal diet was 0.08 mg/kg).Different levels of selenium supplementation had no significant difference on rabbits’average daily food intake (ADFI) (P=0.1202), but average daily gain (ADG) and feed/gain were significantly better when selenium levels were 0.15 and 0.30 mg/kg (P=0.0194, P=0.0401). The dietary selenium levels had significant influence on glutathione peroxidase (GSH-Px) activity of liver, serum and muscle (P=0.0114 , P=0.0009, P<0.0001), superoxide dismutase (SOD) activity of liver and serum (P=0.0323, P=0.0149) and catalane (CAT) activity of liver (P=0.0434). The malonaldehyde (MDA) content of liver and muscle (P=0.0291, P=0.0190) and the total antioxidant capacity (T-AOC) (P=0.0376) were significantly affected by the dietary selenium levels. The dietary selenium levels had significant influence on muscle water loss ratio (P=0.0325) and drip loss (P=0.0042) and the muscle water loss ratio in 0.15 mg/kg group was lower than those in no add of selenium and 0.60 mg/kg groups. The shear value of muscle was significantly affected by the dietary selenium levels (P=0.0285) and the value in selenium supplemented groups were lower than that in no add of selenium group. With the increase of dietary selenium levels, the selenium concentration of the muscle and liver increased with the highest concentration in 0.30 mg/kg selenium added group. Rabbits’serum total cholesterol (TC) (P=0.0497) and density lipoprotein (LDL-C) (P=0.0386) were lower and serum total protein (TP) (P=0.0338), high density lipoprotein (HDL-C) (P=0.0235) was higher when feed forage supplemented with different selenium levels. Dietary selenium supplementation had no influence on triglyeride (TRI) (P=0.0895). Selenium supplementation can low the concentration of serum tetraiodothyronine (T4) (P=0.0327), and increase the concentration of serum triiodothyronine (T3) (P=0.0107), but it had no influence on serum thyrotrophic-stimulating hormone (TSH) (P=0.5981). Liver GSH-Px mRNA expression of 2 to 3 month-old rabbits was significantly affect ted by different selenium supplementation levels (P<0.0001), with the highest expression in 0.15 mg/kg group. In conclusion, the appropriate supplementation of selenium in diet of 2 to 3 months old growing meat rabbits was 0.15 mg/kg (The concentration of selenium in basal diet was 0.08 mg/kg).更多还原