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71.
本试验旨在研究4种不同复合微生物制剂对薯渣与大豆秸秆混贮发酵效果的影响。试验采用密封塑料桶进行混贮,将薯渣与大豆秸秆按照1∶3的重量比混合,采用单因素试验设计,分别设置对照组(不含微生物制剂)及试验1、2、3和4组(分别添加微生物制剂1、2、3、4),每组3个重复。贮存60 d后取样分析,采用实验室化学分析法测定混贮饲料的发酵品质和营养成分,采用半体内法测定48 h瘤胃降解率,同时进行有氧稳定性测试。结果表明:1)各复合微生物制剂组的感官评定结果无明显差异,均为一级优良。2)经发酵品质的分析测定,各复合微生物制剂组的混贮饲料发酵品质均得到改善,以试验2组的pH最低(P<0.01),乳酸含量最高(P<0.01),氨态氮/总氮最低(P>0.05)。3)除试验4组外,各复合微生物制剂组的干物质损失率(DML)均高于对照组(P>0.05),与对照组相比,各复合微生物制剂组粗蛋白质(CP)含量提高(P>0.05),而可溶性碳水化合物(WSC)含量极显著降低(P<0.01),中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)含量无显著差异(P>0.05)。4)各复合微生物制剂组的有氧稳定性较对照组均得到提高,其中以试验2组的效果最好(P<0.01),其次是试验1组(P<0.01)、试验3组(P<0.01)和试验4组(P<0.05)。5)各复合微生物制剂组的干物质(DM)48h瘤胃降解率极显著高于对照组(P<0.01),CP瘤胃降解率(P<0.05)、NDF瘤胃降解率(P<0.01)与对照组相比均以试验2组最高,且试验2组的ADF瘤胃降解率显著高于对照(P<0.05),但与其他组差异不显著(P>0.05),各复合微生物制剂组的淀粉瘤胃降解率较对照组均得到提高,试验2组的淀粉瘤胃降解率较对照组提高3.34%(P<0.01)。综上,在本试验条件下,经发酵处理后,薯渣混贮饲料质地松软,呈酸香味,无黏手现象,试验2组对薯渣与大豆秸秆混贮饲料的发酵品质有明显的改善作用,处理效果最好。  相似文献   
72.
青霉素菌体蛋白营养价值评定及应用效果研究   总被引:1,自引:0,他引:1  
分析结果表明:青霉素菌体蛋白含粗蛋白质41.0%,钙1.44%,总磷1.11%,代谢能水平为9.96KJ/g,5种主要的氨基酸含量如下:赖氨酸1.84%,蛋氨酸0.60%,胱氨酸0.62%,苏氨酸1.78%,色氨酸0.50%;表观消化率分别为:88.4%,90.7%,61.9%,80.4%,91.4%。通过饲养实验说明,在蛋鸡全价料中添加3%、5%、7%的青霉素菌体蛋白,可获得不低于玉米-豆粕日粮的生产成绩  相似文献   
73.
通过肉牛粪污好氧堆肥发酵,对接种不同腐熟剂与空白处理堆肥过程进行物理化性质分析比较,研究不同腐熟剂接种对堆肥过程的影响。结果表明:向堆肥物料中添加腐熟剂可加快堆肥升温速度,提高水分散失率、有机质降解速率,加快粪污腐熟进程,缩短堆肥周期;自主研发腐熟剂和市售腐熟剂堆肥效果相似,项目组自主研发腐熟剂具有加速肉牛粪污腐熟进程的功效。  相似文献   
74.
This study was conducted to investigate the effects of compound p1ant nutrients (CPN) on rumen fermentation parameters, rumen microbiota and fatty acid composition of longissimus dorsi musc1e in finishing sma11 tai1 Han sheep. Sixteen 4-month-o1d finishing sma11 tai1 Han sheep with an initia1 body weight (BW) of (24.18±0.31) kg were random1y divided into two groups, name1y, with 8 rep1icates per group and 1 sheep per rep1icate. The sheep in the contro1 group were fed a basa1 diet, whereas the sheep of the contro1 group (CPN group) was fed the basa1 diet supp1ementation with 3‰ CPN. The experiment 1asted for 97 days after 7 days adaption. The resu1ts showed as fo11ows: compared with the contro1 group, 1) adding CPN decreased the concentration of ammonia nitrogen (NH3-N) (P<0.05); 2) CPN supp1ementation affected beta diversity of rumen microbiota; 3) the re1ative abundance of Acidobacteriota, Erysipe1otrichaceae_UCG-002, Lactobacillus, and Megasphaera were enhanced by adding CPN (P<0.05), whereas, the re1ative abundance of Bacteroidetes and Prevotella was 1ower (P<0.05); 4) the supp1ementation of CPN had no significant effect on fatty acid composition of longissimus dorsi musc1e of fattening sma11-tai1ed Han sheep (P>0.05); 5) the contents of tota1 MUFA, C18:1n9c, C14:1, C16:1, C18:2n6c, C18:3n3 and n-3PUFA in the longissimus dorsi musc1e were corre1ated with the re1ative abundance of Megasphaera, Erysipe1otrichaceae_UCG-002, Succiniclasticum and Ruminococcus (P<0.05). In conc1usion, CPN can regu1ate the rumen microbiota structure and reduce the rumen NH3-N concentration of fattening sma11-tai1ed Han sheep. In production practice, CPN can be used as a rumen eco1ogica1 regu1ator. © 2023 Authors. All rights reserved.  相似文献   
75.
本文研究了6株不同饲用乳酸茵固态发酵棉籽粕产有机酸情况。结果表明:德氏乳杆菌产酸量最高,可达18.56g/kg。为了增加产酸量,利用响应面分析法对德氏乳杆菌固态发酵棉籽粕培养基进行了优化,建立了二次回归方程:Y1=25.07—1.0325*X1—0.47625*X2—1.28875*X5—1.8;5125*X1*X1+0.67*X1十X2+O.17*X1*X5—1.59575.X2*X2-0.6775.X2*X3—1.06;575*X5*X3,并确定了最佳培养基配方为:棉粕916.44g/kg,麸皮83.56g/kg,糖蜜27.91g/kg,水480.24g/kg。在此条件下,使德氏乳杆菌固态发酵棉籽粕产有机酸含量达到25.64g/kg,比优化前提高了39.65%。  相似文献   
76.
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   
77.
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   
78.
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   
79.
本试验旨在研究不同比例青稞秸秆替代苇状羊茅对全混合日粮青贮早期发酵品质及有氧稳定性的影响。试验设对照组(TH0)和3个青稞秸秆不同比例替代组TH5、TH10和TH15。青贮14 d开窖取样,分析其发酵品质、化学成分及微生物数量,将剩余的发酵TMR暴露于空气,用多通道温度记录仪记录温度变化;并分别在有氧暴露的第2,5和8天取样评定其有氧稳定性。结果表明,与对照组(TH0)相比,TH5的pH、乳酸、乙酸、总挥发性脂肪酸和乙醇含量无显著(P>0.05)差异;TH10和对照相比pH差异不显著(P>0.05),但乳酸、乙酸、总挥发性脂肪酸和乙醇含量显著(P<0.05)低于对照组;TH15 pH显著(P<0.05)高于对照组,乳酸、乙酸、总挥发性脂肪酸和乙醇含量显著(P<0.05)低于对照组;各组氨态氮/总氮和乳酸/乙酸无显著(P>0.05)差异,均以乳酸发酵为主,发酵品质良好。有氧暴露第2天后各组pH和氨态氮/总氮持续上升;乳酸、乙酸和水溶性碳水化合物含量持续下降;酵母菌和好氧细菌数量显著(P<0.05)升高。除TH15外,其他各组温度在第35 h开始上升,TH15温度上升延迟,并且温度上升峰值最小。和其他组相比,TH15有氧稳定性最好。综合考虑发酵品质、有氧稳定性及对青稞秸秆资源的最大化利用,建议采用TH15设计配方最为适宜。  相似文献   
80.
The present study aimed to assess the palatability of sausages undergoing low‐temperature fermentation and drying process. Lactobacillus sakei D‐1001 or Lactobacillus salivarius A001 were used as starter cultures for fermentation, and the following properties of the sausages were investigated: colony‐forming units of lactic acid bacteria; concentrations of lactic acid, protein, peptides, and free amino acids; distribution of protein; composition of free amino acids; and physical properties and taste. Alterations in the composition of proteins, peptides, and free amino acids as well as in various physical properties were caused by fermentation by lactic acid bacteria. A sensory test indicated that the palatability of the fermented sausages was greater than that of the non‐fermented sausages, particularly in terms of hardness and juiciness. This was considered to be due to protein degeneration and changes in the physical properties of the sausages as a result of fermentation by lactic acid bacteria. However, the taste of the fermented sausages was sourer than that of the non‐fermented sausages, and therefore, inferior. Our study revealed that the palatability of the sausages in terms of hardness and juiciness were increased by low‐temperature fermentation by lactic acid bacteria and the drying process.  相似文献   
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