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81.
选取28日龄健康杜长大三元杂交仔猪40头,随机分为4组,每组10头。36~39日龄中药组(Ⅲ、Ⅳ组)分别在基础日粮中添加0.5%、1.0%"猪康散",40日龄除阴性对照组(Ⅰ组)外均滴鼻接种PRRSV SCM株1.0mL。于40、45、50、55、60日龄每组选取4头仔猪,前腔静脉采血测定血清细胞因子(IL-2、IL-6、IFN-γ、TNF-α)的变化。结果显示,在整个试验期间,除0.5%中药组40日龄仔猪血清中IL-2含量与阴性对照组差异不显著外(P0.05),0.5%和1.0%中药组仔猪血清中IL-2、IL-6、IFN-γ、TNF-α的含量均显著高于阴性对照组和阳性对照组(P0.01或0.05);除两中药组40日龄仔猪血清中IL-6含量差异不显著外(P0.05),1.0%中药组仔猪血清中IL-2、IL-6、IFN-γ、TNF-α含量均显著高于0.5%中药组(P0.01或0.05)。结果表明,在断奶仔猪基础日粮中添加0.5%和1.0%质量分数的"猪康散"能明显提高人工感染PRRSV仔猪血清中IL-2、IL-6、IFN-γ、TNF-α的含量,从而提高仔猪机体免疫功能,达到抗PRRSV的能力。  相似文献   
82.
A 6‐week broiler study was conducted to evaluate whether subjecting the intestinal microflora of broilers to the effect of weekly variations in feed ingredients could be ameliorated by the inclusion of yeast‐derived feed additives: a yeast cell wall extract (YCW), live yeast culture (LY) or their combination (YCW + LY). Recent changes in ingredient prices have motivated producers to formulate diets not necessarily based primarily on corn and soya bean meal. Intestinal microflora in birds can vary significantly based on the ingredient composition of their diet, and the make‐up of the flora can influence overall bird performance. Within the three nutrient phases of this study, birds were fed either a traditional corn–soya ingredient profile or a variable‐ingredient regimen, which had weekly changes in the ingredient composition. There were consistent ameliorative effects of the yeast treatments in both the corn–soya and the variable‐ingredient groups throughout all 6 weeks, with the YCW + LY combination showing a reduced effect when compared to either product fed alone. The effectiveness of YCW and LY on ameliorating the effects of weekly ingredient variations appeared most effective during the starter and grower phases, but was less significant during the sixth week.  相似文献   
83.
To investigate the pathogen of bovine respiratory disease complex (BRDC) of a dairy farm in Guangxi, a strain of Mycoplasma and a strain of gram-negative pathogenic bacterium were isolated and identified by the means of field surveys, clinic observation, pathological examination, isolation studies and so on.Treatments were taken according to drug sensitivity test results.The Mycoplasma strain, growing on PPLO medium, formed typical "fried egg" colonies.A 448 bp of oppF fragment was amplified by PCR from the strain and had 98.4% nucleotide identity with Mycoplasma bovis reference isolate PG5 of USA.The biochemical features of the gram-negative bacterial isolate were same with Serratia marcescens.The PCR amplified 16S rDNA of the gram-negative pathogenic bacterium strain was 1 400 bp.It shared 99.0% nucleotide identity with other Serratia marcescens reference strains obtained from GenBank.Animal experiment showed that the gram-negative pathogenic bacterium isolate could cause the mice to die.The drug sensitivity tests showed all isolates were sensitive to spectinomycin, azithromycin, amikacin, gentamicin and neomycin.It was effective to treat with dexamethasone and spectinomycin.Pathogen analysis and drug treatment showed that the BRDC was caused by Mycoplasma bovis and Serratia marcescens.  相似文献   
84.
为了研究复合益生菌菌液对奶牛产奶量、乳品质量、牛群健康和肠道菌群的影响,选择20头条件相近的健康奶牛随机分为试验组和对照组,采用菌液与饲料混合的方法饲喂牛群,考察其对奶牛产奶量,肠道菌群乳品质量和牛群健康的影响。结果表明,食用复合益生菌液的每头牛比对照组平均每天可以多产2.9kg牛奶,提高产奶量14.8%,差异极显著(P0.01),经济效益显著;复合益生菌菌液可以促进肠道菌群调整,使有益菌-主要是乳酸菌成为优势菌群,并可以抑制霉菌和降解霉菌毒素,降低牛乳中体细胞数,预防隐性乳腺(房)炎。  相似文献   
85.
为研究人工组合复合菌系降解木质纤维素的效果以及降解过程中微生物群落变化特征。首先对天然复合菌系PLC-8进行分离纯化,随后将筛选出的5株细菌和2株真菌进行组合,构建3 种简化的复合菌系,分别为F1、F2和F3。随后,设计秸秆降解试验,利用DGGE方法测定3种复合菌在分解纤维素过程中微生物群落的变化特征,并进行相关的理化分析。结果表明:人工组合复合菌系F3分解木质纤维素的能力最强,在分解木质纤维素30 d内秸秆平均减重率为39.80%,半纤维素下降52.64%,纤维素下降25.8%,木质素下降6.26%。在第15 天时纤维素内切酶、纤维素外切酶、滤纸酶、β-葡萄糖苷酶、木聚糖酶的活性已经达到整个分解过程的最高值,分别为0.09、0.08、0.09、0.07和0.11 U/mL。复合菌系F3能够自我调节pH,从而改变溶液的pH从微酸性至微碱性,F3的微生物群落呈现出真菌-细菌稳定共存的状态,并且能够长时间保持稳定。因此,人工组合复合菌系F3是稳定、高效的木质纤维素降解复合菌系。  相似文献   
86.
为确定肉食综合体项目现实意义,分析了河南省南阳市内乡县楼房式肉食综合体工艺设计及其生产流程,结果表明内乡县畜牧经济已实现由要素驱动型增长向经济创新型发展。内乡县肉食综合体的建设加强了内乡县经济发展要素保障,初步解决了内乡县区域经济发展瓶颈问题,确定了现代生猪产业发展的新走向。   相似文献   
87.
以糖精、恩诺沙星1:2(W/W)制备恩诺沙星糖精复合物。采用x射线粉末衍射、差式扫描热量法、红外分析法进行表征,同时采用抑菌实验和餐食量实验来进一步表征。抑菌实验表明复合物的抑菌作用是原料药的1.6倍左右,餐食量实验表明复合物的餐食量是原料药的1.5倍左右。恩诺沙星糖精复合物制备工艺简单,能够掩盖药物的苦味,适口性好,改善了药物的难溶性。  相似文献   
88.
几种淡水鱼血清免疫复合物的初步研究   总被引:3,自引:1,他引:3       下载免费PDF全文
采用SDS-PAGE技术和免疫酶斑点法(Dot-ELISA),对罗非鱼、草鱼、鲫、镛和鲤5种淡水鱼的血清免疫复合物(IC)进行了研究。结果表明,鲤科的4种鱼之间的电泳条带差异较小,丽鱼科的罗非鱼与鲤科的4种鱼之间的电泳条带有差异但较小。2%PEG能较好地沉淀5种鱼血清IC,且不同鱼血清IC含量有一定的差异。  相似文献   
89.
利用稻瘟病菌分泌途径相关的调控因子分泌复合物进行生物信息学分析及相关基因定位初探.经同源比对获得稻瘟病菌中分泌复合物8个亚基的同源蛋白,通过在线工具分析蛋白结构域、构建系统进化树、预测亚细胞定位;利用公共数据库获得其在稻瘟病菌不同组织和发育阶段的表达情况;此外,亚细胞定位分析表明,稻瘟病菌分泌复合物亚基MoSec15可能定位于菌丝体的内膜结构中.  相似文献   
90.
The purpose of this study was to investigate the nature of variably sized pigmented foci encountered in fillets of farmed Atlantic salmon, Salmo salar L. The material was sampled on the fillet production line and on salmon farms from fish with an average size of 3 kg from various producers. The fish had been routinely vaccinated by injection. Gross pathology, histology, immunohistochemistry using antisera against major histocompatibility complex (MHC) class II beta chain and transmission electron microscopy (TEM) were used to characterize the changes. Macroscopically, melanized foci were seen penetrating from the peritoneum deep into the abdominal wall, sometimes right through to the skin, and also embedded in the caudal musculature. Histological investigation revealed muscle degeneration and necrosis, fibrosis and granulomatous inflammation containing varying numbers of melano-macrophages. Vacuoles, either empty or containing heterogeneous material, were frequently seen. The presence of abundant MHC class II+ cells indicated an active inflammatory condition. TEM showed large extracellular vacuoles and leucocytes containing homogeneous material of lipid-like appearance. The results showed that the melanized foci in Atlantic salmon fillet resulted from an inflammatory condition probably induced by vaccination. The described condition is not known in wild salmon and in farmed salmon where injection vaccination is not applied.  相似文献   
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