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141.
为研究饲料中添加益生菌对锦鲤幼鱼生长性能和相关免疫基因表达的影响,以初始体重为248.13±4.71 g的锦鲤幼鱼为研究对象,在小型循环水养殖池进行60 d的养殖试验。对照组投喂无益生菌添加的普通商品饲料,试验组投喂在普通饲料中添加枯草芽孢杆菌(Bacillus subtilis)、丁酸梭菌(Clostridium butyricum)和粪肠球菌(Enterococcus faecalis)、枯草芽孢杆菌/丁酸梭菌/粪肠球菌(1∶1∶5)配制成的4组试验饲料,试验饲料的益生菌最终浓度为109 CFU/mL。结果表明,单一菌种或复合菌种的益生菌对锦鲤幼鱼的生长均有显著的促进作用(P<0.05),且对各组血液中酚氧化酶原(phenoloxidase activating system,proPO)、溶菌酶(lysozyme,LZM)和肝脏中抗菌肽(hepcidin)的相对表达量均显著上调(P<0.05),对各组肠道中GST相对表达量有所升高。与对照组相比,复合益生菌效果最好,增重率最高为38.13%,特定生长率提高25.58%,血液中proPO和LZM相对表达量分别升高3倍和2倍之多(P<0.05),肠道中谷胱甘肽S-转移酶(glutathione S-transferase,GST)相对表达量升高了32.45%(P<0.05),肝脏中Hepc相对表达量升高了76.82%(P<0.05)。试验结果提示,在饲料中添加单一/复合益生菌,均可有效提高锦鲤幼鱼的生长性能,以复合益生菌使用效果更好,且proPO、LZM、GST和Hepc免疫基因相对表达量在不同程度上均高于对照组,可见枯草芽孢杆菌、丁酸梭菌和粪肠球菌可以作为益生菌应用于锦鲤养殖。  相似文献   
142.
为促进凉茶渣在畜牧业中的资源化利用,本研究以黑曲霉为菌种固态发酵凉茶渣,首先在单因素试验条件下考察了时间、温度、含水量、浸泡液pH、氮源和碳源对凉茶渣降解率和产物pH的影响;再根据单因素试验结果和规模化生产实际需要,以4%硫酸铵为氮源,2%葡萄糖为碳源,以降解率为考察指标,通过正交试验优化发酵工艺;并通过检测超氧自由基清除率、羟基自由基清除率和1,1-二苯基-2-三硝基苯肼(DPPH)自由基清除率,评价凉茶渣在最优工艺条件下发酵前后抗氧化活性的变化。结果发现,含水量为60%,浸泡液pH为9.0,31℃发酵168 h是凉茶渣的最佳发酵工艺参数。最佳工艺条件下凉茶渣的降解率为25.23%,发酵产物pH为4.53。当凉茶渣发酵前水提液浓度为24 mg/mL时,超氧自由基清除率为43.56%,羟基自由基清除率为47.06%,DPPH自由基清除率为90.71%;当最优条件下发酵产物水提液浓度24 mg/mL时,超氧自由基清除率为30.77%,羟基自由基清除率为95.63%,DPPH自由基清除率为87.36%。本试验结果表明,黑曲霉是适宜的凉茶渣发酵菌种,且凉茶渣经过黑曲霉发酵后具有良好的抗氧化活性。  相似文献   
143.
试验旨在探索羊源D型多杀性巴氏杆菌入侵宿主脾脏组织中引发的免疫应答途径。首先利用羊源D型多杀性巴氏杆菌(HN01菌株)感染小鼠,建立羊源D型多杀性巴氏杆菌感染的动物模型;之后利用转录组测序技术获得感染小鼠与正常小鼠的脾脏转录组数据,并使用COG、KOG、eggNOG、GO、KEGG数据库对测序结果中的差异表达基因(differentially expressed genes,DEGs)进行功能注释与分析,同时对于显著富集到关键免疫通路的差异表达基因使用STRING软件和KEGG mapper进行蛋白互作分析,筛选出核心通路中起关键作用的基因;最后选取关键的10个基因进行实时荧光定量RT-PCR验证。转录组分析结果显示,与正常组相比,感染组中筛选出3 380个差异表达基因(P<0.01,log2|FoldChange|≥0.5),其中1 691个基因上调,1 689个下调。基因功能富集分析结果表明,感染组脾脏中的差异表达基因主要发挥信号转导的功能,其主要参与的生物途径包括细胞因子与细胞因子受体互作通路、趋化因子信号通路、HIF-1信号通路、TNF信号通路。蛋白互作分析筛选出约28个核心差异表达基因,结合实时荧光定量RT-PCR验证后,其中9个基因的表达结果与测序一致,分别是C3、Cd4、Cxcl13、LckGnai1、Grap2、IL-6、Cxcr6及Serping1基因。本研究初步证明了脾脏在抵抗多杀性巴氏杆菌入侵中参与了一系列免疫应答反应,为进一步研究羊源D型多杀性巴氏杆菌与宿主之间相互作用的分子机制奠定理论基础。  相似文献   
144.
1-day-old SPF chickens and commercial Jingfen chickens were vaccinated with IBD immune complex(IC) vaccine, NDV La Sota vaccine were inoculated simultaneously every one week and every two weeks.NDV La Sota immunization alone was as the control group.At the 2nd, 3rd, 4th and 5th week post inoculation, blood samples were taken and the ND HI antibody were tested.Experimental chickens were challenged with high virulent NDV at the 5th week post inoculation, the protective rate of each group was calculated.The results showed the ND HI antibody were not significant different in the combined immunization of IBD IC vaccine priming and NDV La Sota vaccine boost and NDV La Sota vaccine alone immunization (P>0.05).The results indicated that IBD IC vaccine has no immunosuppression on NDV La Sota vaccine in SPF chickens and commercial Jingfen chickens.  相似文献   
145.
This experiment was designed to study the complex of Lactobacillus rhamnosus fermented herbal and Bacillus subtilis on White Feather broiler immunity performance and impact of Escherichia coli infection.360 one-day-old broiler chickens were randomly divided into 3 groups with 4 replicates in each group and 30 chickens per replicate.The pretrial period lasted for 7 d,and the experiment lasted for 35 d.The chickens in the group Ⅰ(positive control group) and group Ⅱ(negative control group)were all only fed a basal diet,group Ⅲ was test group,by additive 1% fermented herbal preparations,groups Ⅱ and Ⅲ were intraperitoneal injection of 1 mL E.coli at 35 d,broiler mortality,immune organ index,cecalmicroflora content,immunoglobulin levels,IL-2 and IL-6 content were tested.The results showed that injection of E.coli caused massive death of chickens,group Ⅱtook up to 75.00%,it was significantly higher than groups Ⅰ and Ⅲ (P < 0.05),the mortality in group Ⅲ was significantly lower than group Ⅱ(P < 0.05),was only 23.33%.Injection of E.coli maked spleen index and thymus index of group Ⅱincreased significantly (P < 0.05),the spleen index and thymus index of groups Ⅰ and Ⅲ were no significant difference (P > 0.05).E.coli counts was significantly decreased after injectionin group Ⅲ (P < 0.05),but the number of intestinal Lactobacilli of group Ⅲ was significantly increased (P < 0.05),and inhibited the propagation of E.coli,the counts of E.coli in groups Ⅰ and Ⅲ were no significant difference (P > 0.05).At 42 d,the sIgA of the intestinal fluid in group Ⅲ were higher than that of groups Ⅰ and Ⅱ with 11.99% and 36.56%,respectively(P < 0.05).The serum IgG concentrations of group Ⅲ was higher than that of groupsⅠand Ⅱwith 14.68% and 28.15%,respectively(P < 0.05).At 42 d,the IL-2 content of group Ⅱ was the lowest,it was significantly lower than group Ⅲ(P < 0.05),the IL-6 of group Ⅲ was significantly lower than group Ⅱ(P < 0.05).  相似文献   
146.
This study was conducted to determine if humoral antibody response of foot-and-mouth disease (FMD) vaccine improved in 8-week-old growing pigs born to well-vaccinated sows pre-treated with 60 mg of poly-γ-glutamic acid (γ-PGA) three days before vaccination. Antibody against FMD virus serotype O was measured 0, 2, 4 and 6 weeks post-vaccination, using a PrioCHECK FMDV type O ELISA kit. The results showed that positive antibody reactions against FMDV serotype O antigen among a component of the vaccine significantly increased in response to pre-injection with γ-PGA.  相似文献   
147.
This trial was conducted in a 2 × 3 + 1 factorial arrangement based on a completely randomized design to evaluate the effects of different dl ‐selenomethionine (dl ‐Se‐Met) and sodium selenite (SS) levels on growth performance, immune functions and serum thyroid hormones concentrations in broilers. A total of 840 Ross 308 broilers (7 days old) were allocated by body weight to seven treatments (three replicates of 40 birds each treatment) including (1) basal diet (containing 0.04 mg of selenium (Se)/kg; control) without supplementary Se; (2, 3 and 4) basal diet + 0.05, 0.15 or 0.25 mg/kg Se as SS; (5, 6 and 7) basal diet + 0.05, 0.15 or 0.25 mg/kg Se as dl ‐Se‐Met. The experiment lasted 42 days. The results revealed that dietary Se supplementation improved (p < 0.05) average daily gain, feed efficiency, immune organ index, serum immunoglobulin A (IgA), immunoglobulin G (IgG), immunoglobulin M (IgM) and triiodothyronine (T3) concentrations and decreased (p < 0.01) thyroxine (T4)/T3 ratio in serum compared with the control. Broilers receiving the dl ‐Se‐Met‐supplemented diets had higher (p < 0.05) feed efficiency, thymus index, the amounts of IgA, IgG, IgM and T3 as well as lower (p < 0.05) serum T4 concentrations and T4/T3 ratio than those consuming the SS‐supplemented diets. Serum IgA and IgM levels of broilers fed 0.15 mg Se/kg were significantly higher (p < 0.05) than those of broilers fed 0.05 or 0.25 mg Se/kg. In summary, we concluded that dl ‐Se‐Met is more effective than SS in increasing immunity and promoting conversion of T4 to T3, thus providing an effective way to improve the growth performance of broilers. Besides, based on a consideration of all experiment indices, 0.15 mg Se/kg was suggested to be the optimal level of Se supplementation under the conditions of this study.  相似文献   
148.
The objective of this study was to evaluate the effects of two different probiotic micro‐organisms on the performance, egg quality and blood parameters of organically reared hens. A total of 900 16‐week‐old Hy‐Line layer hybrids were randomly assigned to three groups of 300 birds each. The control (CTR) group was fed a corn–soya bean cake‐based diet; the L group was fed the same diet supplemented with 0.1% Lactobacillus acidophilus, while the B group was fed the same diet supplemented with 0.05% Bacillus subtilis. Data were recorded at the beginning (weeks 5 and 6: T1) and at the end (weeks 19 and 20: T2) of the experiment, and no differences in hen performance were recorded between dietary groups or sampling times. All of the investigated clinical chemistry parameters, except GGT, were affected by diet (p < 0.05), with the best results recorded for the probiotic‐treated groups. The immune‐response values showed higher blood bactericidal activity in the B and L groups at T2 (p < 0.05) and a lower lysozime concentration in the B group at T1. Higher antibody production against Newcastle disease virus was observed in the L group compared to the CTR (p = 0.013). No differences in oxidative status were recorded, and no effects of diet on egg quality were observed. Among the physical egg characteristics, only the Roche scale colour was affected by diet (p < 0.05): the egg yolk was paler in the L group. The age of the hen was the most relevant factor affecting physical egg characteristics. The chemical parameters of the egg were almost unaffected by supplementation with probiotics except for the lipid content, which decreased with the L diet (p < 0.05). Both probiotic inclusions had beneficial effects on hen metabolism and welfare, and L. acidophilus induced the best immune response.  相似文献   
149.
广州近代城市公园设计精巧,风格独特,在岭南造园史上具有重要地位。结合历史图文资料,运用风景园林史学和风景园林美学相结合的研究方法,归纳分析其造园特征。广州近代城市公园的中西合璧特征主要体现在3个方面:因地制宜的空间布局、中西融合的建筑小品、多姿多彩的植物景观。探析其中西合璧特征,有利于丰富岭南近代园林历史与理论研究,推进对广州近代城市公园的保护与造园智慧的传承。  相似文献   
150.
本试验旨在研究苏氨酸和异亮氨酸对皖西白鹅屠宰性能、器官指数及肠道形态结构、消化酶活性、抗氧化和免疫指标的影响。选取30日龄体重相近的皖西白鹅180只,随机分为3组,每组3个重复,每个重复20只。对照组饲喂基础饲粮,苏氨酸组在基础饲粮中添加2.0 g/kg的L-苏氨酸,异亮氨酸组在基础饲粮中添加2.5 g/kg的L-异亮氨酸。试验期60 d。结果表明:1)各组之间90日龄屠宰性能和器官指数无显著差异(P>0.05)。2)异亮氨酸组60日龄十二指肠和空肠绒毛高度、隐窝深度显著或极显著高于对照组(P<0.05或P<0.01),苏氨酸组60日龄十二指肠、空肠和回肠隐窝深度及90日龄十二指肠和回肠绒毛高度显著或极显著高于对照组(P<0.05或P<0.01)。3)苏氨酸组和异亮氨酸组60、90日龄十二指肠胰蛋白酶活性极显著高于对照组(P<0.01),苏氨酸组60、90日龄十二指肠麦芽糖酶活性及90日龄空肠淀粉酶、乳糖酶活性显著或极显著高于对照组(P<0.05或P<0.01)。4)异亮氨酸组60日龄空肠总抗氧化能力显著高于对照组和苏氨酸组(P<0...  相似文献   
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