[目的]了解鸡粪堆肥过程中不同发酵阶段优势细菌群落的变化情况,为改善鸡粪堆肥工艺及提高堆肥效率提供参考依据.[方法]对不同发酵时间鸡粪堆肥样品进行细菌高通量测序,分析其Alpha多样性和相对丰度,并对获得的有效序列在门、纲、目、科、属、种水平进行聚类,使用LEfSe(LDA effect size)分析不同发酵时间样品间的物种相对丰度差异,从而进一步分析鸡粪堆肥过程中的优势菌群落特征和变化情况.[结果]鸡粪堆肥在各发酵阶段的细菌群落多样性一直处于动态变化中,其中,堆肥上层和中层的细菌群落多样性均呈先上升再下降最后又略微上升的变化趋势,下层的细菌群落多样性表现与上层和中层相反.在门水平,鸡粪堆肥的厚壁菌门(Firmicutes)在各发酵阶段均为主要类群,变形菌门(Proteobacteria)和拟杆菌门(Bacteroidetes)的相对丰度在高温阶段降低,首次在鸡粪堆肥中发现厌氧的盐厌氧菌门(Halanaerobiaeota)且其相对丰度随着堆肥时间的延长逐渐上升.在属水平,鸡粪堆肥起始阶段的优势菌属为乳杆菌属(Lactobacillus)及一些潜在的致病菌属如肠球菌属(Enterococcus)、埃希氏-志贺菌属(Escherichia-Shigella)、韦荣氏球菌属(Veillonella)和库特氏菌属(Kurthia),其相对丰度均随着堆肥时间的延长逐渐下降,并被堆肥后期的优势菌群盐胞菌属(Halocella)和芽孢杆菌属(Bacillus)替代.LEfSe分析也表明,堆肥发酵能降低鸡粪中潜在的致病菌属相对丰度.[结论]鸡粪在堆肥过程中其细菌群落结构随着发酵时间的延长发生变化,厚壁菌门为鸡粪堆肥各阶段的主要类群,变形菌门和拟杆菌门主要存在温度较低的发酵阶段.首次发现盐厌氧菌门在堆肥过程中的相对丰度占比较高,并随着堆肥时间的延长逐渐升高.堆肥发酵能显著降低鸡粪潜在病原菌属的相对丰度.

鸽子在我国有着2000多年的养殖历史,我国是世界最大的肉鸽生产和消费大国,年出栏商品肉鸽数量达6.26亿羽,广西种鸽养殖规模也稳居全国第二位.虽然目前鸽子养殖仍属于小众养殖,但由于鸽子养殖成本低、周期短、见效快和效益高,近些年得到了飞速的发展,已经成为特种养殖的核心产业.随着鸽子养殖集约化程度的提高,鸽子的饲养管理和疾病的防控就显得尤为重要.本文通过总结鸽子养殖过程中饲养管理与疫病防控的要点,旨在减少养鸽生产中的经济损失,为科学、高效益养鸽提供参考.

为获得猪伪狂犬病病毒(Pseudorabies virus,PRV)并初探其病原特性,利用PCR方法检测广西贵港某猪场送检的死亡仔猪病料,随后将组织悬液接种PK-15细胞分离病毒,传到F4代后进行病毒效价测定及小鼠感染试验.结果表明,病料经PCR检测发现呈PRV核酸阳性,组织悬液接种PK-15细胞后,细胞出现固缩、变圆、脱落,形成小合胞体等细胞病变,测定F4代PRV的半数组织细胞感染量(TCID50)为1×10-7.66/100μL,感染的昆明小鼠出现了奇痒、啃咬注射处、皮肤出血甚至死亡等.成功分离得到1株猪伪狂犬病病毒并初探了其病原特性,为今后广西地区猪伪狂犬病病毒的相关研究积累了材料.

为了研究在日粮中添加益生菌对清远麻羽雏鸡生长性能的影响,试验将160只1日龄清远麻羽雏鸡随机分为4组,分别为对照组(饲喂基础日粮)、抗生素组(基础日粮+氟苯尼考200 mg/kg)及益生菌Ⅰ组(基础日粮+益生菌Ⅰ 750 mg/kg,益生菌Ⅰ含有枯草芽孢杆菌和地衣芽孢杆菌,活菌数≥2×109 cfu/g)和益生菌Ⅱ组(基础日粮+益生菌Ⅱ500 mg/kg,益生菌Ⅱ含有乳酸片球菌和乳酸杆菌,活菌数≥3×109cfu/g),每组设置4个重复.试验期为42 d,于21日龄和42日龄时称重检测清远麻羽雏鸡的生长性能,于42日龄时采血检测血清免疫指标,采集盲肠内容物检测其微生物多样性.结果表明:与对照组相比,在42日龄时,益生菌Ⅰ组、益生菌Ⅱ组和抗生素组清远麻羽雏鸡的平均日增重分别提高了 4.78％、6.79％和5.41％,均差异不显著(P＞0.05);益生菌Ⅰ组和益生菌Ⅱ组料重比分别降低了 5.51％、5.15％(P＜0.05),抗生素组降低2.57％(P＞0.05).益生菌Ⅰ组白细胞介素-4(IL-4)含量较对照组提高24.03％(P＜0.05),较抗生素组提高18.93％(P＞0.05);γ干扰素(IFN-γ)含量较对照组降低16.20％(P＞0.05),较抗生素组降低22.82％(P＜0.05).益生菌Ⅱ组IL-4含量较对照组和抗生素组分别提高10.14％和5.61％,差异不显著(P＞0.05);IFN-γ含量较对照组降低13.34％(P＞0.05),较抗生素组降低20.19％(P＜0.05).抗生素组清远麻羽雏鸡肠道菌群OUTs数、Shannon指数和Chao1指数低于益生菌组和对照组.益生菌Ⅰ组和益生菌Ⅱ组的厚壁菌门相对丰度较对照组分别提高24.92％和55.12％,差异显著(P＜0.05).益生菌Ⅰ组梭杆菌门相对丰度较对照组降低15.51％,差异不显著(P＞0.05);益生菌Ⅱ组较对照组降低24.40％,差异显著(P＜0.05).益生菌Ⅱ组变形菌门相对丰度较对照组降低41.69％,差异显著(P＜0.05).抗生素组的副拟杆菌属相对丰度分别较对照组、益生菌Ⅱ组和益生菌Ⅰ组提高64.70％、19.63％和73.43％,差异显著(P＜0.05).说明益生菌可提升清远麻羽雏鸡的生长性能、免疫性能,且能丰富雏鸡盲肠菌群多样性.

饲料是畜牧业发展的必要支撑资料,也是影响动物健康以及动物产品安全的重要因素,他不仅影响动物和动物产品的销售,而且在受到污染时会危害动物甚至人类的健康.目前,饲料受到霉菌毒素污染进而影响动物健康问题突出,文章综述当前我国饲料被霉菌毒素污染的现状、霉菌毒素检测现状以及当前应对霉菌毒素污染饲料的措施.

试验旨在探究VA5免疫增强剂对鸽新城疫病毒(NDV)灭活疫苗(ND4416株)的免疫增效作用.选取160只健康鸽随机分为4组:ND4416株灭活疫苗组(NDV组)、ND4416株灭活疫苗与免疫增强剂(VA5)混合组(NDV+VA5组)、La Sota灭活疫苗组(La Sota组)及生理盐水空白对照组(C组),进行免疫效力及免疫持续期试验.采用血凝抑制试验检测各组鸽免疫后不同时间点的血清抗体效价,结果显示,VA5免疫增强剂能够显著提高鸽NDV灭活疫苗血清抗体水平(P＜0.05).脾脏淋巴细胞转化试验结果显示,VA5能够有效刺激免疫鸽的淋巴细胞转化.在免疫后第30、90、180天,各组鸽子采用ND4416株进行攻毒试验,结果显示,NDV+VA5组在3个时间点的攻毒保护率均为100％,均高于La Sota组.免疫持续期试验结果显示,NDV+VA5组血清抗体水平在免疫后第21天达峰值11.201og2,第180天仍能达到7.501og2,攻毒保护率达100％,表明VA5免疫增强剂可延长鸽新城疫疫苗的免疫效力持续期至180 d.攻毒后体外排毒检测结果表明,VA5免疫增强剂能够缩短攻毒后鸽的体外排毒周期,减少体外排毒.综上,VA5免疫增强剂能够显著提高鸽NDV灭活疫苗的免疫效果,为研制效果更好的鸽NDV疫苗提供了基础依据,同时也为免疫增强剂的应用增加了试验数据.

[目的]探究水提和乙醇提八角精油对三黄鸡生长性能、免疫性能及肠道菌群的影响.[方法]选用21日龄广西三黄鸡150只,随机分为5组,每组3个重复(10只/重复).在不同试验组鸡的饲料中分别添加八角精油(乙醇提)0.4g/kg、八角精油(水提)0.4g/kg、八角精油(水提)0.8g/kg、抗生素0.06g/kg及空白对照组等5个试验组.[结果]经过21d的试验发现,八角精油0.8g/kg水提组ADFI和F/G较空白对照组降低了9.3％、10.5％(P<0.05);八角精油水提0.4g/kg和0.8g/kg组血清免疫球蛋白A比空白对照组分别提高了36.4％、44.9％(P<0.05);八角精油水提0.4g/kg和0.8g/kg组大肠杆菌菌数,比空白对照组分别降低49.88％和53.23％.[结论]水提八角精油对三黄鸡具有提高生产性能、提升部分血清免疫球蛋白水平,增强免疫性能,优化肠道菌群的作用.

[目的]探究不同的提取方法获得的八角精油间成分的差异,为八角精油在功能和应用研究时,对八角精油不同提取成分需求提供提取参考依据.[方法]通过利用索氏提取法,探究不同的溶剂对八角茴香油的提取率以及提取成分的影响.[结果]试验结果表明,乙醇作为溶剂的八角精油的提取率最高,达到20.65％;其次是乙醚与石油醚溶剂组,分别为19.05％和19.525％.乙醇溶剂组所得的八角精油中的反式茴香脑含量为54.20％,而乙醚与石油醚溶剂组的分别为42.56％和38.9％.[结论]结果表明乙醇提取的八角精油含量最高,抑菌效果最好,在生产应用中应当优先选用乙醇溶剂提取八角精油.

The pigeon circovirus (PiCV) is a member of the genus Circovirus of the family Circoviridae.The PiCV is an immunosuppressive pathogen.In the present study,a polymerase chain reaction(PCR)specific to the PiCV was used to detect samples collected from racing pigeons in Jiangsu Province,China.Six out of 22 samples were positive in PCRs.Total DNA was extracted from the JS15-1 sample and the genome was amplified and sequenced.Complete genome sequences were submitted to the GenBank database (GenBank number KX431143).The full-length of the genome was 2034 bp and contained three main open reading frames.Homology analyses showed that the overall nucleotide identity between this genome and others accessed in the National Center for Biotechnology Information database is ranged from 85.3％ to 97.1％.The best identity was with Bel20,in which the identity of Rep gene nucleotides ranged from 92.1％ to 96.6％ and that of Cap gene nucleotides ranged from 72.2％ to 99.4％.A phylogenetic tree based on the full-length genome also showed that JS15-1 had the closest relationship with the Bel20 that emerged in Belgium in 2006.A phylogenetic tree based on the Rep gene showed that JS15-1 was located in the same branch as Bel20,PiCV/Japan/2010,and Ita4B.A phylogenetic tree based on the Cap gene showed that JS15-1 and Bel20 were in the same branch,and JS15-1 had the closest relationship with Bel20.Compared with Bel20,six amino-acid mutations were found at residues 8,10,53,69,95 and 202 in the Rep protein and one amino-acid was found at residue 33 in the Cap protein.A one amino-acid insertion was found at residue 34 in the Cap protein.These results suggest that JS15-1 may have originated from Belgium,and that JS15-1 was imported from a large number of breeders from Belgium within the last two decades.

One strain of pigeon Newcastle disease virus(NDV) was isolated from a diseased racing pigeon loft suspected to be infected with NDV in Nanjing.This NDV isolate was named Pi/NJ/CH/4416/2016 (ND4416) and purified by using specific pathogen-free(SPF) eggs.Biological tests showed that this isolate showed high pathogenicity to pigeons,but lower to chickens.The resulting RNA samples were converted to cDNAs,followed by PCR amplification and sequencing of F and HNgenes.The cleavage site of the fusion protein(F) was 112RRQKRF117,a feature generally associated with virulent NDV strains.Phylogenetic analysis based on F and HNgene sequences showed that this strain belonged to Class Ⅱ,Ⅵb subgenotype.In addition,Pi/NJ/CH/4416/2016 and other strains prevailing in China were more closely related to the PPMV-1/Belgium/11-09620/2011(JX901124.1) strain.It supported that epidemic pigeon NDV isolates in China might originate from Belgium.Pi/NJ/CH/4416/2016 had a far genetic relationship from the classic vaccine strain La Sota (AF077761.1).Bioinformatics analysis revealed that a linear epitope tope consisting of amino acids 491-500 of HNprotein of this pigeon strain was different from La Sota.In addition,hemagglutination inhibition test revealed a noticeable antigenic difference between them.

江苏省某种鹅场15日龄雏鹅疑似感染鸭疫里氏杆菌,无菌采取脑、心脏、肝和脾等病料,进行病原分离纯化,通过细菌生化试验、血清型鉴定及设计特异性扩增鸭疫里氏杆菌外膜蛋白A(OmpA)基因的引物,进行PCR扩增,从8份病料中分离到2株血清2型鸭疫里氏杆菌.药物敏感性试验表明,2个分离株对红霉素和阿奇霉素的敏感性高于其他药物.对OmpA基因PCR产物进行基因序列测定,在NCBI上进行基因序列同源性比对,其基因序列与多株已发表的序列的同源性达到99％.进化分析表明,分离株均与D2、G2株具有很近的亲缘关系.

为构建新型H7亚型禽流感HA基因的原核表达载体，并在大肠杆菌中进行表达。从NCBI数据库下载H7亚型禽流感HA全基因序列，合成HA基因；定向克隆到原核表达载体pET－32a（＋）的多克隆位点中，构建重组原核表达质粒 pET －32a（＋）－HA；转化入大肠杆菌 BL21（DE3）中经 IPTG 诱导表达，表达产物经 SDS －PAGE 和Western－blot法鉴定。结果显示，重组质粒经双酶切及基因测序鉴定构建正确；重组的HA融合蛋白约为84 ku，大小与预期融合蛋白大小一致；重组HA融合蛋白可以与His标签单克隆抗体特异性结合，与H7阳性血清有较强的反应原性。成功构建了HA基因原核表达载体，并在大肠杆菌BL21（DE3）中获得重组HA融合蛋白表达。