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51.
The effect of hay type on the microbiome of the equine gastrointestinal tract is relatively unexplored. Our objective was to characterize the cecal and fecal microbiome of mature horses consuming alfalfa or Smooth Bromegrass (brome) hay. Six cecally cannulated horses were used in a split-plot design run as a crossover in two periods. The whole plot treatment was ad libitum access to brome or alfalfa hay fed over two 21-d acclimation periods with subplots of sampling location (cecum and rectum) and sampling hour. Each acclimation period was followed by a 24-h collection period where cecal and fecal samples were collected every 3 h for analysis of pH and volatile fatty acids (VFA). Fecal and cecal samples were pooled and sent to a commercial lab (MR DNA, Shallowater, TX) for the amplification of the V4 region of the 16S rRNA gene and sequenced using Illumina HiSeq. The main effects of hay on VFA, pH, and taxonomic abundances were analyzed using the MIXED procedure of SAS 9.4 with fixed effects of hay, hour, location, period, and all possible interactions and random effect of horse. Alpha and beta diversities were analyzed using the R Dame package. Horses fed alfalfa had greater fecal than cecal pH (P ≤ 0.05), whereas horses fed brome had greater cecal than fecal pH (P ≤ 0.05). Regardless of hay type, total VFA concentrations were greater (P ≤ 0.05) in the cecum than in feces, and alfalfa resulted in greater (P ≤ 0.05) VFA concentrations than brome in both sampling locations. Alpha diversity was greater (P ≤ 0.05) in fecal compared with cecal samples. Microbial community structure within each sampling location and hay type differed from one another (P ≤ 0.05). Bacteroidetes were greater (P ≤ 0.05) in the cecum compared with the rectum, regardless of hay type. Firmicutes and Firmicutes:Bacteroidetes were greater (P ≤ 0.05) in the feces compared with cecal samples of alfalfa-fed horses. In all, fermentation parameters and bacterial abundances were impacted by hay type and sampling location in the hindgut.  相似文献   
52.
本试验旨在建立一种利用气相色谱快速检测瘤胃体外发酵液中三甲胺浓度的方法.瘤胃体外发酵试验设置2个组,对照组(n=4)和试验组(n=4),试验组每个发酵瓶中添加0.0414 g三甲胺盐酸盐,发酵24 h.采用10 mol/L氢氧化钾溶液对发酵液样品进行预处理,使用WEL-PEG20M色谱柱和氢火焰离子检测器对三甲胺进行分...  相似文献   
53.
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.  相似文献   
54.
2010年9月1525日,采用瞬时扫描法和所有事件取样法对贺兰山野化牦牛进行行为观察,建立了牦牛的行为谱,并将相关行为进行分类,即运动、摄食、休息、社群和其他行为。研究表明:牦牛秋季昼间行为的分配比例最高为运动行为(39.85±1.73)%,其次是摄食(33.33±2.50)%和休息(23.78±3.75)%行为,社群(0.99±0.27)%和其他(2.05±0.18)%较低。运动在8:0025日,采用瞬时扫描法和所有事件取样法对贺兰山野化牦牛进行行为观察,建立了牦牛的行为谱,并将相关行为进行分类,即运动、摄食、休息、社群和其他行为。研究表明:牦牛秋季昼间行为的分配比例最高为运动行为(39.85±1.73)%,其次是摄食(33.33±2.50)%和休息(23.78±3.75)%行为,社群(0.99±0.27)%和其他(2.05±0.18)%较低。运动在8:0010:00,14:0010:00,14:0016:00时有明显的高峰期,摄食高峰期出现在9:0016:00时有明显的高峰期,摄食高峰期出现在9:0010:00时和15:0010:00时和15:0016:00时,休息在12:0016:00时,休息在12:0013:00时出现高峰期。采用2个独立样本的Mann-WhitneyU检验对不同年龄的牦牛行为进行比较,年龄因素对牦牛运动、摄食、休息和其他行为影响不显著(P>0.05),但对社群行为影响显著(P<0.05)。  相似文献   
55.
添加烟酸条件下绵羊瘤胃发酵底物降解动力学变化特征   总被引:3,自引:0,他引:3  
试验用瘤胃液来自3只安装永久性瘤胃瘘管的绵羊,饲喂玉米-豆粕型基础日粮.通过体外试验,添加450 mg/kg烟酸,测定在不同培养时间内培养液中NH3-N浓度、瘤胃细菌N产量、原虫数量、总VFA量及乙酸、丙酸、丁酸产量和乙酸/丙酸值的降解动力学特征.结果表明:添加烟酸可提高培养液NH3-N利用率;培养液中细菌N、原虫数、总VFA量及乙酸、丙酸、丁酸产量随采样时间变化而呈不同的动力学变化趋势;但乙酸/丙酸值则不受采样时间变化的影响,与对照组相比差异不显著(P>0.05).  相似文献   
56.
糙皮侧耳对几种粗饲料营养成分的影响   总被引:1,自引:0,他引:1  
实验以玉米秸秆,小麦秸秆,干苜蓿为主要研究对象,用糙皮侧耳进行菌化并发酵培养,分析对比菌化前后三种粗饲料在感官指标和营养成分方面的变化情况。结果表明,三种粗饲料被糙皮侧耳菌化后颜色变鲜艳,质地变软,有淡淡的香味;玉米秸秆粗蛋白提高11.70%,粗脂肪提高6.18%,粗纤维降低17.25%,木质素降低6.62%;小麦秸秆粗蛋白提高9.21%,粗脂肪提高5.42%,粗纤维降低17.47%,木质素降低8.07%;干苜蓿粗蛋白提高9.32%,粗脂肪提高5.54%,粗纤维降低14.18%。糙皮侧耳对秸秆的饲料化利用具有重要意义。  相似文献   
57.
本文通过建立体外亚急性瘤胃酸中毒(subacute ruminal acidosis,SARA)模型,研究不同添加水平的石榴皮多酚提取物(pomegranate peel polyphenol extract,PPPE)对SARA相关有害因子的影响.试验采用单因素试验设计,PPPE设3个添加水平,即分别为发酵底物质量的...  相似文献   
58.
为验证不同类型及比例的酵母培养物(YC)对绵羊瘤胃体外发酵参数的影响。采用全因子试验设计,在发酵底物条件下分别添加不同类型及比例的YC,一个对照组、4个试验组,测定体外发酵参数浓度;发现YC-3能极显著降低培养液pH和丙酸浓度,显著增加异丁酸浓度和乙丙比。在体外条件下添加1%、2%YC均能显著增加培养液中乙酸浓度,添加4%YC能极显著降低异戊酸的浓度。YC不同来源和不同水平影响绵羊瘤胃体外发酵pH、丙酸及乙丙比等发酵参数,用于指导畜牧生产实际。  相似文献   
59.
This study examined the differences between non‐inoculated (control) corn and Northern Leaf Blight (NLB)‐damaged corn (inoculated corn); dry matter (DM) yield, silage fermentation quality, nutritive value and feed intake by sheep were compared. Leaf, stem and grain dry weights and gross yield of inoculated corn were significantly (P < 0.05) decreased compared with control corn. The contents of water‐soluble carbohydrate and nitrogen‐free extract (NFE) were decreased in inoculated corn compared with control corn. Silage made from both inoculated and control corn showed good fermentation quality. The digestibility of DM, organic matter, ether extract, NFE, and energy of silage made from inoculated corn were significantly (P < 0.05) lower, and contents of total digestible nutrients (TDN) and digestible energy (DE) were also significantly (P < 0.05) lower compared with silage made from the control corn. DM intake showed no significant discrepancy between the two types of silage. TDN and DE intakes from inoculated silage were significantly (P < 0.05) lower compared with control silage. From the above results it was shown that NLB caused a decrease in DM yield and NFE content in corn and a decrease in the nutritive value and feed intake of silage.  相似文献   
60.
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