Necrotic enteritis challenge regulates peroxisome proliferator-1 activated receptors signaling and β-oxidation pathways in broiler chickens

Necrotic enteritis (NE) is an important enteric disease in poultry and has become a major concern in poultry production in the post-antibiotic era. The infection with NE can damage the intestinal mucosa of the birds leading to impaired health and, thus, productivity. To gain a better understanding of how NE impacts the gut function of infected broilers, global mRNA sequencing (RNA-seq) was performed in the jejunum tissue of NE challenged and non-challenged broilers to identify the pathways and genes affected by this disease. Briefly, to induce NE, birds in the challenge group were inoculated with 1 mL of Eimeria species on day 9 followed by 1 mL of approximately 10⁸ CFU/mL of a NetB producing Clostridium perfringens on days 14 and 15. On day 16, 2 birds in each treatment were randomly selected and euthanized and the whole intestinal tract was evaluated for lesion scores. Duodenum tissue samples from one of the euthanized birds of each replicate (n = 4) was used for histology, and the jejunum tissue for RNA extraction. RNA-seq analysis was performed with an Illumina RNA HiSeq 2000 sequencer. The differentially expressed genes (DEG) were identified and functional analysis was performed in DAVID to find protein–protein interactions (PPI). At a false discovery rate threshold <0.05, a total of 377 DEG (207 upregulated and 170 downregulated) DEG were identified. Pathway enrichment analysis revealed that DEG were considerably enriched in peroxisome proliferator-activated receptors (PPAR) signaling (P < 0.01) and β-oxidation pathways (P < 0.05). The DEG were mostly related to fatty acid metabolism and degradation (cluster of differentiation 36 [CD36], acyl-CoA synthetase bubblegum family member-1 [ACSBG1], fatty acid-binding protein-1 and -2 [FABP1] and [FABP2]; and acyl-coenzyme A synthetase-1 [ACSL1]), bile acid production and transportation (acyl-CoA oxidase-2 [ACOX2], apical sodium–bile acid transporter [ASBT]) and essential genes in the immune system (interferon-, [IFN-γ], LCK proto-oncogene, Src family tyrosine kinase [LCK], zeta chain of T cell receptor associated protein kinase 70 kDa [ZAP70], and aconitate decarboxylase 1 [ACOD1]). Our data revealed that pathways related to fatty acid digestion were significantly compromised which thereby could have affected metabolic and immune responses in NE infected birds.     

肉鸭常见维生素营养代谢病研究进展

维生素是维持肉鸭正常代谢及保持高的生产性能所必需的一类营养物质.在肉鸭养殖过程中,维生素的缺乏或过量都会造成机体产生营养代谢病.文章就肉鸭养殖过程中常见的维生素营养代谢病进行分析,并提出相应的防治措施,从而保障肉鸭的健康养殖.     

日粮蛋白质水平对云南半细毛羊空怀母羊能量代谢的影响

为研究日粮蛋白质水平对云南半细毛羊空怀母羊能量代谢的影响,试验选择25只云南半细毛羊空怀母羊,平均分为5个组,分别饲喂蛋白质水平为8.4％、10.0％、12.3％、13.6％、15.9％的日粮,用全收粪法进行消化代谢试验,试验期共19 d,预试期14 d,正试期5 d.结果表明:(1)日粮蛋白质水平对总能摄入量无显著影...     

Feeding Saccharomyces cerevisiae fermentation products lessens the severity of a viral–bacterial coinfection in preweaned calves

We have previously reported that supplementation with Saccharomyces cerevisiae fermentation products (SCFP) ameliorates clinical signs and lung pathology following experimental bovine respiratory syncytial virus (BRSV) infection in preweaned dairy calves. The objectives of this study were to determine the effect of SCFP supplementation on the metabolic and endocrine responses, and disease outcome of a viral–bacterial coinfection in preweaned calves. Twenty-seven, 1- to 2-d-old Holstein-Angus cross calves were enrolled in the study; one SCFP calf was removed from the trial during the pre-challenge phase due to complications from nephritis. Calves were assigned to two treatment groups: control or SCFP-treated, base milk replacer with 1 g/d SCFP (Smartcare, soluble formula) and calf starter top dressed with 5 g/d SCFP (NutriTek, insoluble formula). Calves were infected with BRSV on day 21, followed 6 d later by intratracheal inoculation with Pasteurella multocida (PM). Calves were euthanized on day 10 post-viral infection. Calves receiving SCFP had reduced thoracic ultrasonography scores on day 7 post-viral infection (P = 0.03) and a tendency toward reduced scores on day 10 post-viral infection (P = 0.09). Calves receiving SCFP also had less severe lung pathology scores at necropsy (P = 0.06). No differences between treatments were observed in lung viral loads (P = 0.48) or bacterial lung recovery (P = 0.34); however, there was a distinction in the lung location for PM recovery, with PM isolated more frequently from the cranial lobes in SCFP-treated calves, but more frequently from the caudal lobes of control calves. Calves treated with SCFP tended (P = 0.07) to have higher serum IL-6 concentrations following the coinfection. Calves treated with SCFP had lower concentrations of serum nonesterified fatty acids and beta-hydroxybutyric acid compared with controls following experimental challenge (P = 0.03 and P = 0.08, respectively), suggesting metabolic changes favoring growth and development. There were no differences between groups in gene expression of insulin receptor, insulin-like growth factor 1 (IGF-1), IGF-1 receptor (IGF-1R), growth hormone receptor, or haptoglobin in the liver. Results from this study suggest that supplementing with SCFP may moderate the impact of a respiratory viral–bacterial coinfection on preweaned calves through metabolic and immune modifications.     

绵羊Musclin基因真核表达载体的构建及其对肌细胞糖代谢和胰岛素作用的影响

为了研究绵羊Musclin对糖代谢和胰岛素作用的影响,本试验运用生物信息学软件对其结构特征进行预测,并构建绵羊Musclin基因真核表达载体.分4组对绵羊胎儿成肌细胞进行处理:空载体组(pcDNA3.1)、Musc-lin 过表达组(pcDNA3.1-Musclin)、空载体+胰岛素组(pcDNA3.1+Insulin...     

光周期与氮肥互作对华农1号青饲玉米碳氮代谢相关酶的影响

于2005年3-7月,采用盆栽试验,设置3个不同光照长度处理和氮素水平,研究了不同光照时数及氮素水平对远缘玉米杂交种华农1号青饲玉米碳氮代谢相关酶活性的影响.结果表明,在苗期,16 h光照处理下植株叶片磷酸烯醇式丙酮酸羧化酶、蔗糖磷酸合成酶、蔗糖合成酶、谷氨酰胺合成酶和硝酸还原酶等酶的活性显著低于13和10 h光照处理;至抽雄期和收获期,13和10 h处理下植株叶片各种酶的活性下降速率较快,而16 h处理下酶活性下降缓慢且显著高于13和10 h处理.在抽雄期或收获期,16 h处理下叶片各种酶的活性均随施氮量的增加而增加,但在13和10 h处理下均有几种酶的活性在高氮素水平下出现下降的趋势.总的看来,在16 h光照处理下,植株苗期碳氮代谢相对较弱,到中后期代谢能力明显提高,且耐高氮能力也较强,收获期植株叶片酶的活性显著高于13和10 h处理.     

不同饲喂方式对南方奶牛产奶性能、养分消化和代谢的影响

研究了具有南方奶牛日粮类型特征的相同精粗比日粮的不同饲喂方式对奶牛的采食行为、产奶性能、全肠道养分表观消化率和血清代谢产物的影响。选用体重相近的12头荷斯坦奶牛,采用单因子设计,根据产奶量、胎次及泌乳天数随机分为2组（n=6）,分别为精粗分饲组（SI）和全混合日粮组（TMR）,精饲料：粗饲料均为50：50。试验结果表明：奶牛采食量无差异,在相同精粗比日粮下,TMR饲养技术极显著减少了奶牛的采食时间（P〈0.01）,显著增加了反刍时间（P〈0.05）,TMR组奶牛的乳脂率、4%标准奶产量、乳脂产量、乳糖产量和乳固形物产量分别比SI组显著提高11.20%、11.60%、17.50%、13.21%和9.86%（P〈0.05）,但对奶牛咀嚼行为、全肠道养分表观消化率和血清代谢产物影响不显著（P〉0.05）。在南方奶牛典型日粮采用TMR饲养技术时,与精粗分饲相比,可提高奶牛的产奶性能,但对奶牛的采食量、咀嚼行为、全肠道养分表观消化率和血清代谢产物没有显著影响。     

OPG/RANKL/RANK系统的生理功能

骨是一个代谢活跃的器官,在整个生命周期中都在进行不断的更新与重建。在骨形态发生和重建的过程中主要受到细胞因子和激素的调节,同时骨代谢也受到OPG/RANKL/RANK系统的调控。论文主要对骨骼生理结构与骨组织细胞之间的关系,骨代谢和骨的形成过程,OPG/RANKL/RANK系统的生理功能,OPG/RANKL/RANK系统的影响因子以及骨代谢紊乱所引起的疾病几个方面作一综述。     

三聚氰胺的毒理学研究进展

三聚氰胺(MA)化学性质稳定,在体内代谢不活泼,能以原体或同系物形式从尿液排出体外,在F344大鼠血浆中的半衰期为2.7h,在肾脏的清除率为2.5mL/min;MA对小鼠的半数致死量(LD50)为4550mg/(kg.bw),在国际化学物质急性毒性分级中属低毒性物质,接近微毒;MA对家兔、豚鼠和人眼无刺激作用;与三聚氰酸同时存在时毒性增加,毒性作用的靶器官为膀胱和肾脏;MA致癌性研究文献较少,结果也不一致,国际癌症研究中心认为MA对动物有致癌的可能性,但没有证据表明对人类有致癌作用。目前的研究认为,MA对环境和人的潜在危险性较小。对国内外关于三聚氰胺毒性的研究概况进行了总结,并综述了MA的污染及代谢、毒性和检测方法。     

褐藻胶低聚糖生物活性研究进展

综述近年来褐藻胶低聚糖在抑菌、抗肿瘤、调节免疫、促生长、抗氧化等生物活性方面的研究,展望褐藻胶低聚糖的应用前景。