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101.
102.
Jiao Song Xin Lei Jingxian Luo Nadia Everaert Guiping Zhao Jie Wen Ye Yang 《Journal of animal physiology and animal nutrition》2019,103(4):1030-1038
This study was to investigate the effects of Epigallocatechin‐3‐gallate (EGCG) on intestinal morphology, antioxidant capacity and anti‐inflammatory response in heat‐stressed broiler. A total of 192 2‐week‐old Arbour Acres broilers chickens were divided into four groups with six replicates per group and eight chickens per replicate: one thermoneutral control group (28°C, group TN), which was fed the basal diet; and three cyclic high‐temperature groups (35°C from 7:00 to 19:00 hr; 28°C from 19:00 hr to 7:00 hr, heat stress group), which were fed the basal diet supplementation with EGCG 0 mg/kg (group HS0), 300 mg/kg (group HS300) and 600 mg/kg (group HS600). The gut morphology and intestinal mucosal oxidative stress indicators, as well as intestinal barrier‐related gene expression, were analysed. The results showed that compared with group TN, heat stress reduced the villus height (VH), activities of glutathione peroxidase (GSH‐Px), superoxide dismutase (SOD)and catalase (CAT), increased the crypt depth (CD) and malondialdehyde (MDA)content at 21, 28 and 35 days (p < 0.05). After the heat‐stressed broilers were supplemented with EGCG, VH, VH/CD (V/C), and the activities of GSH‐Px, SOD and CAT were increased, and CD and MDA content were reduced compared with those in group HS0 without EGCG supplementation at 21, 28 and 35 days (p < 0.05). The EGCG supplementation promoted the gene expression of nuclear factor‐erythroid 2‐related factor 2 (Nrf2), Claudin‐1, Mucin 2 (Muc2) and alleviated the nuclear factor‐kappa B (NF‐κB) and lipopolysaccharide‐induced tumour necrosis factor (LITAF) gene expression compared with group HS0 (p < 0.05). Moreover, intestinal morphology was strongly correlated with antioxidant ability and inflammatory response. In conclusion, EGCG alleviated the gut oxidative injury of heat‐stressed broilers by enhancing antioxidant capacity and inhibiting inflammatory response. 相似文献
103.
云豌1号是以食荚90-17(无须蔓生品种)为母本,以食荚大菜豌(矮生品种)为父本进行杂交,经系统选育而成的矮生无须菜用豌豆新品种。植株直立矮生,株高50~60 cm,复叶无须(即卷须退化),营养体发达,叶片肥厚,嫩梢纤维少,幼苗质地柔软,食用品质佳,VC含量34.9 mg · kg-1,总黄酮含量3?290 mg · kg-1。一般每667 m2可产嫩尖850~1?200 kg,适宜云南省海拔1?100~2?400 m的豌豆产区或南方生境相似的秋播豌豆产区种植。 相似文献
104.
Modulation of broilers’ caecal microflora and metabolites in response to a potential probiotic Bacillus amyloliquefaciens 下载免费PDF全文
G. T. Cao X. A. Zhan L. L. Zhang X. F. Zeng A. G. Chen C. M. Yang 《Journal of animal physiology and animal nutrition》2018,102(2):e909-e917
Studies have found that a dietary supplement of Bacillus amyloliquefaciens improved the growth performance, increased the nutrient digestibility of hosts and modulated the intestinal microflora. A total of 360 1‐day‐old Ross broilers were randomly divided into three treatments: a control group with a basal diet, an antibiotic group with a basal diet and added colistin sulphate, and a probiotics group with a basal diet and added Bacillus amyloliquefaciens. The HiSeq high‐throughput sequencing analysis of 16S rRNA was used to investigate the differences in birds’ caecal microflora, and metabolomics was used to analyse changes in caecal metabolites. Results showed that the supplementation of Bacillus amyloliquefaciens significantly improved the BW and ADG compared with the control birds. Results of sequencing indicated that (i) 645, 670, 596 unique operational taxonomic units (OTUs) were found in birds supplemented with Bacillus amyloliquefaciens on day 7, 21 and 42, separately, (ii) due to the diversity and relative abundance of the birds’ caecal microflora, the OTUs of the caecal microflora clustered according to age and treatment, except on day 42, (iii) among the six predominate families (Ruminococcaceae, Lachnospiraceae, Enterobacteriaceae, Erysipelotrichaceae, Lactobacillaceae and Rikenellaceae), the supplementation of Bacillus amyloliquefaciens significantly increased Enterobacteriaceae on day 42, (iv) Bacillus amyloliquefaciens increased the relative abundance of Faecalibacterium and Ruminococcus on day 21, increased the Faecalibacterium and Blautia and decreased the Ruminococcus on day 42. The metabolomics of caecal metabolites showed that the dietary Bacillus amyloliquefaciens changed the caecal metabolites involved of amino acid metabolism and glyceride metabolism, and the antibiotics changed the caecal metabolites that were related to carbohydrates and amino acid metabolism on day 21. 相似文献
105.
采用RT-PCR方法对2009—2011年山西省分离的5株猪繁殖与呼吸综合征病毒(Porcine reproductive and respiratory syndrome virus,PRRSV)的ORF5和Nsp2(2503~3269nt)基因进行克隆和测序,并对其基因序列和推导的氨基酸序列与国内外毒株进行了同源性分析。序列分析结果显示,5株分离株Nsp2基因与国内分离的PRRSV变异株(JXA1、HuN、HUN4、HUB1)的序列同源性最高,为96.8%~98.2%,且缺失位置一致,均存在2个位点30个氨基酸缺失;ORF5基因大小为603bp,编码200个氨基酸,第13、151位均为具有强毒特性的精氨酸(R),137位为丝氨酸(S),表明这5株均为野毒株,与国内分离的PRRSV变异株(JXA1、HuN、HUN4、HUB1)毒株的序列同源性最高,为96.5%~98.0%。结果表明,山西省内目前流行的PRRSV为Nsp2缺失30个氨基酸的变异毒株。 相似文献
106.
107.
Polysulfonamide (PSA) has been widely used in many fields because of its excellent thermodynamic properties. In this study, PSA fibers were prepared separately via two different spinning ways, including conventional wet spinning and electrospinning. Fluid motion of wet spinning and electrostatic field of electrospinning were modeled using finite element analysis to investigate the spinning process. The properties of fabricated PSA fibers were characterized systematically by scanning electron microscope (SEM), fourier transform infrared spectrometer (FTIR), X-ray diffraction (XRD), thermal gravity analysis (TGA) and electronic strength tester. Based on the simulation and theoretical analysis of spinning process, it was found that the extruding force of the wet spinning is larger than that of the electrospinning. The larger extruding force makes the alignment of macromolecules inside fiber relatively uniform, and a higher proportion of crystallization happens. Accordingly, the mechanical properties and thermal stability of PSA fibers could be improved due to a higher proportion of crystallization. The experimental results of mechanical strength and TG test are coincided with the simulation results. PSA fiber prepared by wet spinning has better thermal stability and mechanical properties than that fabricated by electrospinning. 相似文献
108.
对集成地理信息系统(GIS)技术应用于新疆棉花施肥专家系统(ES)进行了研究和探讨,通过Internet访问该专家系统界面,用户可以得到农田地块的地理信息,进行棉田施肥推荐;同时可进行农田肥力的综合查询和专题图制作。该专家系统的建立不仅推进了新疆地区平衡施肥信息化的进程,也为精准农业的实践提供决策支持。 相似文献
109.
采用22种限制性内切酶分析了三江白猪线粒体DNA的多态性。结果表明:在60头个体中检出30种限制性态型.归结为7种基因单倍型;其间的差异来自少数限制性位点的突变。单倍型间平均遗传距离为0.35%,群体遗传多态程度为0.044%。三江白猪遗传多样性非常贫乏,说明三江白猪与地方种猪起源于一个共同祖先,在品种形成早期受到创立者效应的制约。 相似文献
110.