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1.
The present study was designed to investigate the potential application of native (N) and recombinant (truncated modified [tmFliC] and full-length [flFliC]) flagellin proteins along with inactivated Newcastle disease virus (NDV). Fifty six SPF chickens were immunized twice with PBS (control), inactivated NDV (Ag), inactivated NDV/flFliC (AgF), inactivated NDV/tmFliC (AgT), inactivated NDV/N (AgN), commercial vaccine containing Montanide (Vac) and Vac/N (VacN), with a two-week interval. Blood was collected weekly and spleens were harvested after chickens were sacrificed. Interleukin-6 (IL-6) and tumor necrotic factor-α (TNF-α) gene expression in peripheral blood mononuclear cells were analyzed by Real-Time PCR. Antibody response was assessed by haemagglutination inhibition (HI). Cellular activity was quantified by MTT assay. Results showed that the most IL-6 and TNF-α gene expression was observed in AgF group (P < 0.01). The lowest gene expression among vaccinated groups was observed in Ag group for IL-6 and Ag and Vac group for TNF-α. The highest HI titer was observed in Vac, VacN, AgF and AgT groups. The AgF group showed the highest cellular activity (P < 0.01). In conclusion, flagellin-adjuvanted groups showed a pro-inflammatory effect and acted similarly to or better than the Vac group. Hence, flagellin can be proposed as a potential adjuvant for ND vaccine.  相似文献   
2.
An enriched environment is widely used to improve domestic animals’ welfare and promote their natural behaviors. Music can reduce abnormal behavior in humans, nonhuman primates, and rodents. However, little is known about the effects of music on pigs. This study aims to explore the effects of repeated music stimulation on the behavior, physiology, and immunity of growing pigs. A total of 72 hybrid piglets (Large White × Duroc × Minpig) were randomly divided into three groups, including music (Mozart K.448, 60 to 70 dB), noise (recorded mechanical noise, 80 to 85 dB), and control (natural background sound, <40 dB), and 6 h sound stimulation was given per day (1000 to 1600 hours) from 40 to 100 d of age. The behavioral activities of the pigs were observed during the music stimulation, and their serum cortisol, salivary cortisol, and serum immune indices were also measured. Compared with the control group, the music group and noise group increased activity but decreased lying of pigs (P < 0.05). A significant increase in tail-wagging, playing, and exploring behaviors of pigs was found in the music group (P < 0.05), and the noise significantly increased the aggressive behavior of the pigs (P < 0.05). Tail-wagging, playing, exploring, manipulating, and aggressive behaviors decreased over time. Short-term (8 d) music stimulus had a lower cortisol level than that of the noise and control groups (P < 0.05), whereas long-term (60 d) music stimulus increased immunoglobulin G (IgG), interleukin-2 (IL-2), and interferon-gamma (IFN-γ) levels (P < 0.05) and decreased interleukin-4 (IL-4) level (P < 0.05). Long-term noise stimulus significantly reduced the level of IgG (P < 0.05) but did not affect the level of IL-2, IL-4, and IFN-γ levels (P > 0.05). In conclusion, short-term music stimulus (8 d) reduced the stress response, whereas long-term music stimulus (60 d) enhanced the immune responses. In addition, the noise increased the aggressive behavior, and long-term noise reduced the immunity of the growing pigs.  相似文献   
3.
轮状病毒(RV)是引起婴幼儿、幼畜禽急性肠胃炎的人畜共患病原,常与其他病原体混合感染,多以呕吐,严重水样腹泻,脱水为临床症状,感染后具有较高病死率,对人类公共卫生以及养殖业造成极大危害。RV病原相关分子模式(PAMP)可被肠上皮细胞(IECs)中一组可遗传的模式识别受体(PRR)识别,通过IECs、先天免疫细胞与RV互作,激活细胞内信号级联,从而迅速诱导炎症和多种抗病毒基因表达。论文就轮状病毒特性、肠道先天免疫等方面进行综述,探讨RV感染宿主IECs后诱导不同抗病毒信号通路,为利用先天免疫途径预防轮状病毒感染提供了一定的参考。  相似文献   
4.
为了探讨添加红枣提取物对促进虹鳟(Oncorhynchus mykiss)机体健康的可能性,选取体长为7.2~8.4 cm的健康虹鳟,随机分成4个试验组,分别投喂红枣提取物添加量为0%(对照组)、0.25%、0.50%和1.00%的等氮等脂饲料,饲养56 d,养殖结束后测定12项血清生化指标和头肾的6个免疫相关基因mRNA表达量。结果显示:与对照组相比较,血清中肌酐(CREA)和尿素氮(BUN)含量三个红枣提取物组均出现极显著下降;谷丙转氨酶(GPT)活性在0.50%和1.00%组极显著下降,谷草转氨酶(GOT)活性也在0.50%和1.00%组出现了一定程度下降,但差异不显著;酸性磷酸酶(ACP)和碱性磷酸酶(AKP)活性无显著变化;总蛋白(TP)和白介素6(IL-6)含量在0.25%组出现显著增加;溶菌酶(LZM)活性三个红枣提取物组均显著升高;超氧化物歧化酶(SOD)活性在0.50%组极显著增加;补体4(C4)和肿瘤坏死因子(TNF-α)含量在0.25%和0.50%组均极显著增加。在头肾中,与对照组相比,SOD、白介素1β(IL-1β)和补体3(C3)基因表达量在0.50%和1.00%组均为显著或极显著上调;Factor H基因表达量在0.50%组显著上调;过氧化氢酶(CAT)和LZM基因表达量在0.50%和1.00%组仅出现差异不显著上调。上述结果表明,在虹鳟饲料中添加一定量的红枣提取物,可以起到促进肾功能,保护肝脏和提高其非特异性免疫功能的作用。  相似文献   
5.
试验旨在研究日粮添加N-乙酰半胱氨酸(NAC)对早期断奶仔猪的氧化还原状况和免疫指标的影响。试验选取10窝仔猪,随机分为2组,每组5窝,对照组饲喂基础日粮,试验组从7日龄开始,至25日龄时结束,在基础日粮中添加500mg/kg NAC。仔猪21日龄断奶。25日龄时,每窝选取1头(每组共5头),采集血样和脾脏样。结果表明,日粮添加NAC组显著提高了血清谷胱甘肽过氧化酶(GSH-Px)和超氧化物歧化酶(SOD)水平(P0.05),降低了丙二醛(MDA)和过氧化氢(H2O2)(P0.05)的含量,同时增加了血清中免疫球蛋白IgM的含量(P0.05),而对仔猪血清炎性因子水平无显著影响。NAC处理能显著提高脾脏中IL-2,IL-6及I-κBαmRNA的相对表达水平(P0.05)。上述结果表明,日粮中添加500mg/kg NAC显著提高了断奶仔猪的抗氧化能力和免疫力,缓解断奶应激。  相似文献   
6.
病害是危害农业生产的重要因素之一,植物对于病原菌的抗性依赖于植物的天然免疫(plant innate immunity)系统。因此,对于植物天然免疫的研究将为农作物抗病育种提供重要理论基础。植物天然免疫系统包含彼此相互关联的两个层面,即PTI(PAMP-triggered immunity)和ETI(effector-triggered immunity)。近年来,国内外对于PTI的研究取得了一系列重要进展。PTI是由病原物相关分子模式PAMP(pathogen-associated molecular pattern)所诱发的植物免疫反应。PAMP被位于植物细胞表面的受体识别后,将免疫信号通过胞质类受体激酶BIK1(Botrytis-induced kinase 1)、MAPK级联、CDPK(calcium-dependent protein kinase)等向下游传递,诱导活性氧的爆发、气孔的关闭、免疫基因的表达等,从而抑制病原微生物的生长。免疫信号在传递过程中会在多个层次上被精细调控,以保证合适的反应强度和持续时间。本文从植物免疫受体FLS2及其他免疫受体的发现、免疫信号转导组分的发现以及其生物学功能、参与天然免疫的转录因子、植物免疫反应的负调控及植物天然免疫在抗病育种中的应用等方面综述了近年来植物PTI天然免疫的分子机理和信号转导方面的研究进展。并对该领域的发展提出展望,我们认为农作物天然免疫信号转导和作物与致病真菌互作系统的研究将会是未来研究的重点和主要方向,天然免疫的重要理论与基因编辑技术的结合,必将使作物抗病育种迎来新时代。  相似文献   
7.
大口黑鲈饲料中2种植物性蛋白质混合物替代鱼粉的研究   总被引:2,自引:0,他引:2  
为了探讨在大口黑鲈饲料中去皮豆粕分别与玉米蛋白和大米蛋白组成的2种植物性蛋白质混合物替代鱼粉的可行性,分别于含45%和30%鱼粉的配方中配比上述2种植物性蛋白质混合物,配制成4种等氮等能的饲料。用上述饲料饲养初始体质量为(58.69±0.07)g的大口黑鲈53 d。结果显示:30%鱼粉组的终末体质量和特定生长率显著高于45%鱼粉组(P0.05),而饲料效率、蛋白质效率、蛋白质消化率和氨基酸消化率之间无显著性差异(P0.05)。玉米蛋白组的饲料效率和蛋白质效率显著高于大米蛋白组(P0.05),而摄食量显著低于大米蛋白组(P0.05)。全鱼和肌肉的粗蛋白质、粗脂肪、水分和灰分各组间差异不显著(P0.05)。30%鱼粉组的血清溶菌酶活性和血清蛋白含量显著高于45%鱼粉组(P0.05),而玉米蛋白组和大米蛋白组对血清溶菌酶活性和血清蛋白含量的影响差异不显著(P0.05)。红细胞数和红细胞压积各组间差异不显著(P0.05)。本研究表明,去皮豆粕分别与玉米蛋白和大米蛋白组成的植物性蛋白质混合物可以使大口黑鲈饲料中的鱼粉含量由45%降至30%;去皮豆粕与玉米蛋白组成的植物性蛋白质混合物的替代效果优于去皮豆粕与大米蛋白组成的植物性蛋白质混合物。  相似文献   
8.
The aim of this study was to determine the best synbiotic combination (based on growth and short‐chain fatty acids production) between Enterococcus faecalis and eight prebiotics. Based on the results of in vitro studies, E. faecalis + galactooligosaccharide (EGOS) and E. faecalis + mannanoligosaccharide (EMOS) were selected as synbiotics. A 126‐day feeding trial was conducted to compare the effects of prebiotics, probiotic and synbiotics on the growth indices, In vivo ADC of nutrients, digestive enzymes, hemolymph indices and finally, biological responses against 48‐hr Aeromonas hydrophila exposure challenges of juvenile (4.13 ± 0.12 g) crayfish. The highest values of SGR (2.19% body weight day?1), VFI (2.75% body weight day?1), survival rate (96.67%) and the lowest FCR (2.33) were observed in the juvenile crayfish fed the EGOS‐ diet. The significantly (p < .05) highest means of in vivo ADCOM, in vivo ADCCP, in vivo ADCCF and in vivo ADCGE were measured in crayfish fed the EGOS‐ diet. The mean survival rate of Aeromonas hydrophila‐injected crayfish fed the EGOS‐ diet (56%) was significantly (< .05) higher than those of fed the control (8.67%) and other diets (22.67–35.32%). At the levels tested, 7.86 log CFU E. faecalis g?1 + 10 g kg?1 GOS in the diet was considered optimum.  相似文献   
9.
目的 探讨蜂胶类黄酮对糖尿病合并肺结核(diabetes mellitus complicated with pulmonary tuberculosis,DM-PTB)患者外周血中WBC与T淋巴细胞亚群的影响。方法 以DM-PTB患者120人为对象,利用随机数字表采用完全随机法分成A(蜂胶黄酮1 000 mg/d)、B(蜂胶黄酮2 000 mg/d)、C(条件对照)三组,每组40人,观察6个月,比较综合治疗前后白细胞计数(WBC)及分类(淋巴细胞L和中性粒细胞N)、T淋巴细胞亚群CD3+、CD4+、CD8+数量及CD4+/CD8+比值的变化,并比较组内前后差异和组间差异。结果 三组7项观测指标自身前后配对差值(治疗后-治疗前)的均数比较Hotelling T2=515.359,P=0.000;治疗7项观测指标差别Wilks λ=0.017,P=0.000,其中多重比较结果为WBC的B组大于A与C组,L的B组> A组> C组,N的B组大于A与C组,CD3+的B 与A组大于C组,CD4+的B组>A组>C组,CD4+/CD8+比值多重比较结果为B 与A组大于C组。结论 蜂胶类黄酮能提高DM-PTB患者的细胞免疫水平。  相似文献   
10.
An 8‐week feeding trial was conducted to investigate the effects of dietary chitosan oligosaccharide complex with cerium (Ce IV) (COS‐Ce) on growth performance, nonspecific immunity and disease resistance of sea cucumber, Apostichopus japonicas. Five isonitrogenous (18.6%) and isolipidic (1.1%) practical diets were formulated with graded level of COS‐Ce (0, 150, 300, 600 and 1200 mg kg?1 dry feed), which were named as COS‐Ce/0, COS‐Ce/150, COS‐Ce/300, COS‐Ce/600, COS‐Ce/1200 respectively. Each diet was allocated to four replicates of sea cucumbers (Initial weight: 6.72 ± 0.02 g). Sea cucumbers were fed to apparent satiation once daily (19:00 hours) for 56 days. During the experiment, water temperature was kept at 16 ± 0.5°C, pH 7.8–8.2, dissolved oxygen beyond 5 mg L?1, ammonia nitrogen below 0.5 mg L?1 and salinity from 30‰ to 31‰. Results showed that the specific growth rate of sea cucumbers was significantly higher in COS‐Ce/600 than that in other four treatments. Activities of phagocytosis, respiratory burst, acid phosphatase and alkaline phosphatase in COS‐Ce/600 were significantly higher than that in COS‐Ce/0 (P < 0.05) respectively. On the contrary, cumulative mortality was the lowest in COS‐Ce/600 following 14 days exposure to Vibrio splendidus (P < 0.05). In conclusion, these results confirmed that dietary COS‐Ce had beneficial effects on growth performance, nonspecific immunity and disease resistance of sea cucumber.  相似文献   
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