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51.
We isolated two pseudorabies virus (PRV) isolates (designated OT-1 and OT-2) from two hunting dogs exhibiting neurological manifestations after eating the flesh of wild boar hunted in Oita prefecture, Kyushu Island, Japan. The isolates corresponded to a previously reported PRV (MY-1 strain) isolated from a hunting dog in neighboring Miyazaki prefecture, and it clustered into genotype II based on the glycoprotein C sequence. Our results suggest that this common PRV strain may have been maintained in wild boars on Kyushu Island even though domestic pigs in this area have attained an Aujeszky’s disease-free status.  相似文献   
52.
对酶提方法的原理、酶类选择依据、酶提工艺,以及酶提法应用现状进行了综述,旨在为同类研究提供技术参考。中草药具有广泛的应用前景和开发潜力,为提高中药疗效,方便临床用药,生产中常需要对中草药进行提取,然而传统的提取方法较为繁杂。随着科技进步,一些现代中药提取方法不断涌现。酶提方法是一种应用酶工程技术提取中药的现代中药提取方法,该方法具有高效、无毒、反应条件温和等优点,是一种发展潜力较大的中药提取方法。  相似文献   
53.
建立了超高效液相色谱-静电轨道阱质谱联用测定禽蛋中五氯苯酚残留量的分析方法。取均质后的禽蛋样品经乙腈溶液提取,加入无水硫酸镁和氯化钠进行脱水和盐析,高速离心分层后,取适量乙腈层溶液经0.1%(V∶V)甲酸稀释后,用酸性氧化铝粉末进行样品净化并以10000 r/min离心取上清液,过0.22μm滤膜后上机测定。使用反相色谱柱进行分离,流动相为乙腈:0.1%甲酸=75∶25,采用等度程序进行洗脱,静电轨道阱质谱进行定性定量分析。结果表明,五氯苯酚在0.5~100μg/kg范围内线性关系良好(r>0.995),方法的最低检出限为0.2μg/kg,最低定量限为0.5μg/kg,添加回收率在74.43%~96.85%之间,批内批间变异系数CV%<10%。该方法具有较好的准确度与精密度,适用于禽蛋中五氯苯酚残留量的测定。  相似文献   
54.
(目的)开发一种具有促生长作用的新中兽药贞芪颗粒,优化其提取工艺并对其促生猪生长作用进行初步研究,为其工业化生产提供参考。(方法)以总多糖、黄芪甲苷、毛蕊异黄酮葡萄糖苷、特女贞苷、红景天苷、干膏得率作为评价指标,采用层次分析法(AHP)、基于指标相关性的权重确定方法(CRITIC)、AHP-CRITIC混合加权法确定各评价指标的权重系数,根据其正交试验结果优化贞芪颗粒提取工艺参数。将100头保育猪随机分为5组,通过在日粮中添加不同剂量的颗粒,连续喂养30天,与空白组和阳性对照组对比,计算平均日增重(ADG)、平均日采食量(ADFI)和料肉比(F: G)。(结果)AHP-CRITIC混合加权法科学优选出最佳提取工艺参数为复方药材加12-13倍质量的水提取3次(第一次13倍),每次2.5 h。3批验证试验综合评分均值为98.91,RSD为0.79%。经过30天饲喂,高、中、低剂量组和阳性对照组的料重比无显著性差异(P>0.05),但都显著低于空白对照组(P<0.05),其中中剂量组的料重比最低。(结论)AHP-CRITIC混合加权法确定的权重系数客观、真实,优选出的贞芪颗粒提取工艺经验证,合理、稳定,重复性好,此工艺条件下制备的颗粒对生猪具有促进生长的作用。  相似文献   
55.
根据国家石漠化综合治理草地畜牧业工程的需要,应用营养学、饲料学等学科理论,本文对贵州喀斯特石漠化地区白酒糟资源的利用价值进行了综合评价,包括其营养价值、饲用价值、生态价值和经济价值。同时针对白酒糟饲料化开发利用过程中存在的加工技术滞后、理论研究不足、地域条件限制等问题进行了分析,提出了运用青贮法和微生物发酵等关键技术、强化基础理论研究、构建饲料加工中心等相应解决对策,并指出大力发展以白酒糟为原料的非常规饲料加工业是喀斯特石漠化地区发展生态畜牧业的重要举措,也是巩固石漠化治理成果的有效办法。  相似文献   
56.
本试验采用柠檬酸提取法和碱提取法从海带中提取多糖组分,以总抗氧化能力和羟自由基(·OH)为衡量抗氧化活性指标,比较这两种提取方法得到海带粗多糖产率和抗氧化活性。试验结果表明:柠檬酸提取法和碱提取法的提取率分别为15.92%和6.05%,所提取的海带粗多糖具有良好的抗氧化活性,且柠檬酸提取法抗氧化活性更高。 [关键词] 柠檬酸提取法|碱提取法|海带多糖|抗氧化活性  相似文献   
57.
The purpose of this experiment was to study the immunization rule of the egg yolk antibody affected by different vaccines,immunization dose and injection ways and further to discuss the optimal immunization procedures of the laying hens for the preparation of egg yolk antibody against swine Japanese encephalitis virus.180 brown laying hens without any vaccines were selected and divided into 18 groups randomly,each group of 10 hens.Groups 1,2 were the control groups,injected with the sterile saline;Groups 3 to 10 were injected with subcutaneous or intramuscular injection,and the vaccine was injected with 0.2,0.5,1.0 and 1.5 mL successively.Groups 11 to 18 were also adopted two kinds of injection,followed by the same dose of vaccine immunization.Six eggs of each experimental group were gathered before immune day and after 3,7,10,14,18,21 and 28 days,the egg yolk antibody was extracted and the titer was determined.As a result,the egg yolk antibody titers of groups 1 to 6,11 and 12 were all 0,and no significant immune response produced;The hens from 7 to 10 groups were injected with the inactivated vaccine.After 7 days,the average antibody titer reached the peak,and the duration of the antibody was 14 days.The hens from 13 to 18 groups were injected with the attenuated virus vaccine.After 14 days,the average antibody titer reached the highest value,and the duration of the antibody was 21 days.The egg yolk antibody titers were not significantly different in the two compared experiment groups with the same injection dose but with different injection ways (P>0.05).With the same injection way of each experiment group,and the difference was significant (P>0.05).Compared with some groups with the same injection and vaccine,the titer of yolk antibody was gradually increased with the increase of the immune dose,and the difference was significant (P<0.05).The results showed that,no matter intramuscular or subcutaneous injection,in order to produce a significant immune response to hens,the immune antigen dose was 1.0 mL inactivated vaccine or 0.5 mL attenuated vaccine at least.Compared with the attenuated and inactivated vaccine,inactivated vaccine stimulated the body to produce the antibody faster,but the maintenance time was shorter;The lower dose of attenuated vaccine could stimulate the body to produce antibodies,but the speed was slower,the maintenance time was longer.  相似文献   
58.
59.
本文综述了近年来黑豆色素的研究进展.提出了综合开发利用的前景.  相似文献   
60.
Comparison of sampling sites and detection methods for Haemophilus parasuis   总被引:3,自引:0,他引:3  
Objective To improve the isolation rate and identification procedures for Haemophilus parasuis from pig tissues. Design Thirteen sampling sites and up to three methods were used to confirm the presence of H. parasuis in pigs after experimental challenge. Procedure Colostrum‐deprived, naturally farrowed pigs were challenged intratracheally with H parasuis serovar 12 or 4. Samples taken during necropsy were either inoculated onto culture plates, processed directly for PCR or enriched prior to being processed for PCR. The recovery of H parasuis from different sampling sites and using different sampling methods was compared for each serovar. Results H parasuis was recovered from several sample sites for all serovar 12 challenged pigs, while the trachea was the only positive site for all pigs following serovar 4 challenge. The method of solid medium culture of swabs, and confirmation of the identity of cultured bacteria by PCR, resulted in 38% and 14% more positive results on a site basis for serovars 12 and 4, retrospectively, than direct PCR on the swabs. This difference was significant in the serovar 12 challenge. Conclusion Conventional culture proved to be more effective in detecting H parasuis than direct PCR or PCR on enrichment broths. For subacute (serovar 4) infections, the most successful sites for culture or direct PCR were pleural fluid, peritoneal fibrin and fluid, lung and pericardial fluid. For acute (serovar 12) infections, the best sites were lung, heart blood, affected joints and brain. The methodologies and key sampling sites identified in this study will enable improved isolation of H parasuis and aid the diagnosis of Glässer's disease.  相似文献   
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