In January 2018,a large-scale abortion occurred in sows in a pig farm in Yulin region, Guangxi Province. The inguinal lymph nodes of newborn piglets turned blue and purple, and the mortality rate reached more than 15%;nursery pigs began to develop fever one week after weaning, with obvious respiratory symptoms and high mortality 20%. In order to diagnose the disease of pigs on the pig farm, the experiment used RT-PCR to determine the pathogen of the infection and analyze its genetic evolution. Based on the diagnosis results, a vaccine immunization and drug treatment plan was formulated and implemented. The effect of the comprehensive prevention and control program was evaluated by the production performance indicators(such as the number of litters within 6 months, average litter size per litter, average healthy litter size per litter, piglet mortality rate in delivery room, and morlality rate of mursery piglets),monitoring the PRRSV pathogen by fluorescent RT-PCR methods, and antibodies in the sow’s serum. The results showed that the pathogen causing reproductive disorders in sows on the farm was PRRSV. Sequencing and genetic evolution analysis of its ORF5 and Nsp2 genes, the sequencing strain was named GXYL 2018, the virus strain and the PRRSV NADC30 2012 strain were on the same evolutionary branch, and the qenetic similarity was 91.7% and 90.6% respectively. After immunization with PRRSV inactivated vaccine and drug treatment programs, sows in the farm showed no symptoms of reproductive disorders. The PRRSV positive rates and antibody dispersion in the serum of sows, gilts and boars decreased by 64.16,48.19,80.00 percentage points, and 38.43,14.76,23.97 percentage points respectively. The number of healthy litters per sow litter increased by 1.61,and the mortality rates of farrowing room and nursery decreased by 9.72 and 10.02 percentage points respectively. The results suggested that PRRSV inactivated vaccine immunization and drug treatment can be used for the comprehensive prevention and control of sow reproductive disorders caused by PRRSV NADC30-like strain.

为了解广西玉林市牛羊口蹄疫(FMD)和小反刍兽疫(PPR)免疫情况,2017—2019年采用酶联免疫吸附试验(ELISA),对从玉林市7个县(市、区)234个种畜场、规模养殖场和散养户采集2244份羊血清和922份牛血清样本进行O型、A型和亚洲I型FMD以及PPR免疫抗体检测,并比较不同年份、不同地区的免疫抗体水平.结果显示:2017—2019年,玉林市牛羊O型FMD抗体场群及个体合格率基本保持在70％以上,但部分地区的抗体合格率较低(P<0.05);亚洲I型FMD抗体合格率2017年偏低,但2018年后直线上升至80％以上;A型FMD抗体合格率普遍较低,均不足70％.PPR免疫合格率逐年增长,均保持在70％以上,且无显著地区差异(P>0.05).结果表明,广西玉林市牛羊O型、亚洲I型FMD和羊PPR的整体免疫效果较好,但A型FMD免疫效果较差,且FMD免疫效果存在一定的地区不均衡性.因此,玉林市应根据各地区实际情况,持续加强FMD、PPR免疫和监测,确保各地区牛羊处于较高的免疫保护水平.本调查为玉林市有效防控此类疫病提供了技术支持.

为了解近年来广西玉林市规模猪场主要病毒性疫病的流行动态和免疫保护水平,分析疫情流行趋势和暴发风险,对2016—2019年采集自玉林市规模猪场284个场次的6954份血清样本,以及113个场次的1539份临床健康猪组织样本、249个场次自主送检的536份病死猪组织样本,进行猪瘟病毒(CSFV)、猪繁殖与呼吸综合征病毒(PRRSV)、猪圆环病毒2型(PCV2)、猪伪狂犬病病毒(PRV)抗体和抗原检测,并对结果进行时间和区间分析.结果显示:2016—2019年,规模化猪场CSFV、PCV2、PRV-gB场群平均抗体阳性率以及个体平均抗体阳性率均在70％以上;PRRSV抗体阳性率总体偏低,但2019年抗体阳性率超过90％.北流市CSFV场群及个体抗体阳性率最低,与其他地区有差异(P<0.05);北流市、福绵区、玉州区的PRRSV场群抗体阳性率未超过70％,低于其他地区(P<0.05);各地区间PCV2抗体阳性率无统计学差异(P>0.05);福绵区PRV-gB抗体阳性率(<70％)与其他地区相比最低(P<0.05);在健康屠宰猪群及病死猪群组织样品中均检出上述4种病原,其中PRRSV、PCV2病原阳性检出率较高.结果表明,玉林市规模化猪场上述4种疫病的免疫抗体保护水平总体较高,但部分地区抗体水平偏低,且均存在猪群带毒现象,尤其是PRRSV、PCV2,存在疫病暴发风险.结果提示,各县(市、区)要根据本地养殖及疫病监测情况,制定科学合理的免疫计划,加强综合防控与监测,防止上述猪群疫病的发生与流行.本研究调查了广西玉林市猪群主要病毒性疫病的免疫保护水平及其病原流行特点,为该地区此类疫病防控提供了数据支持.

猪场生物安全防控是生猪健康养殖的最重要环节.为掌握广西玉林市规模猪场生物安全现状及主要风险因子,通过问卷调查方式,对玉林市83家规模猪场的生物安全状况进行了风险调查与评估.结果显示:广西玉林市规模猪场生物安全高、中、低风险占比分别为12％、42％、46％,主要风险因子为"围墙外未建立绿化隔离带""隔离区在生产区上风向""与其他畜禽养殖场、主干道或居民区的距离在500 m以下""猪场未实行自繁自养""猪场无围墙或防疫沟""场内运输车辆未执行专用且不出场外""猪场猪繁殖与呼吸综合征病原学PCR检测阳性".结果表明,广西玉林市规模猪场应重点从猪场选址、场内布局、设施设备、饲养管理及卫生防疫、免疫等方面进一步提高猪场生物安全水平.

为了解广西玉林市规模化猪场猪繁殖与呼吸综合征病毒(PRRSV)感染情况及其与猪瘟病毒(CSFV)、猪圆环病毒2型(PCV2)和猪伪狂犬病病毒(PRV)混合感染情况,采用RT-PCR/PCR方法,对2016—2018年采集自玉林市存栏母猪300头以上规模化猪场的661份临床健康猪血清样本和896份表现呼吸道症状和繁殖障碍发病猪只的组织样本,进行PRRSV病原检测,并对检出的PRRSV病原阳性样本进行CSFV、PCV2、PRV病原检测,并对结果进行统计分析.结果显示:2016—2018年收集的血清样本中,PRRSV病原阳性率分别为6.86％、19.33％和10.17％,场阳性率分别为25.00％、46.67％和40.00％;PRRSV血清阳性样本混合感染率分别为52.38％、65.22％和62.50％,以与PCV2、PRV混合感染为主.2016—2018年收集的病料组织样本中,PRRSV病原检出率分别为46.38％、48.24％和48.81％,场阳性率分别为42.11％、35.37％、37.10％;PRRSV病料阳性样本混合感染率分别为50.00％、52.99％和52.35％,同样以与PCV2、PRV混合感染为主.结果表明,广西玉林市规模猪场中PRRSV流行广泛且呈加重趋势,与PCV2和PRV等病原的混合感染较严重.结果提示,玉林市规模猪场应制定科学的免疫程序,加强这些疫病的综合防控.

Guangxi is the province most seriously affected by rabies virus (RABV) in China. Those most affected by RABV each year are people in rural areas, where dogs are the main cause of human infection with the virus.

参考GenBank发表的传染性法氏囊病毒(IBDV)基因组序列,设计并合成了一对特异扩增IB-DV VP2基因的引物.以广西玉林发病火鸡群分离的IBDV野毒YL株为材料,以其基因组为模板利用RT-PCR技术扩增出了1.5kb的cDNA产物,将VP2基因克隆于PUC119质粒上,得到重组PUC119质粒.并对VP2基因全序列测定、分析和聚类表明,YL株与欧洲超强毒株非常相似,而与经典强毒株、弱毒株和变异株相差较大.

The N_terminal nucleotides 47～420 of the Guangxi APMV_1 isolates of different poultry species origin were amplified and sequenced.The alignment and phylogenetic analysis of the nucleotide sequences and deduced amino acid sequences of F gene of the Guangxi isolates and other reference strains,obtained from GenBank,were done by using DNAStar(DNASTAR Inc.,Madison,WI).The results indicated that the component and arrangement of amino acid of all Guangxi isolates,at the cleavage site of F gene,have the typical pattern of NDV virulent strains,and were identical with the facts in the field cases.All the Guangxi isolates are classified into genotypeⅦ of APMV_1,the same genotype dominated in China and other areas in recent years.Furthermore,we also found that Mukteswar,a widely used vaccine strain in China,was classified into genotype Ⅶ.The pathogenicities of Guangxi isolates were evaluated based on the classical standards MDT and ICPI,and compared with the results based on the sequence features of cleavage site of F gene and it was found that the former was not identical with the facts in the field cases for some isolates,but the latter was fully identical.

The rapid differential diagnosis technique for detection of virulent and non-virulent NDVs was used to detect 144 clinical samples of avian paramyxovirus type 1 (APMV-1) suspect from different poultry species. Some positive samples were also diagnosed by the classical isolation and identification. The results showed that 64.58% of the samples from chickens, pigeons, geese, ducks, quail, peacock, thrush and ostrich respectively were positive of NDV. 29 Field strains of APMV-1 were isolated from 7 (avian) species origins and some were classified as mesogenic or velogenic strains of NDV by the rapid differential diagnosis technique. The results demonstrated that the developed technique of RT-PCR basis is a specific, sensitive, rapid and reliable for the diagnosis of APMV-1 infections in different poultry species origins and applicable in the laboratory diagnosis.

禽Ⅰ型副粘病毒 (APMV-1) 共有9个血清型,即APMV-1～APMV-9.APMV-1引起的相关疾病主要有鸡新城疫、鹅副粘病毒病、鸽I型副粘病毒病.这三种疾病的病原既为同一血清型,其核苷酸必有较高的同源性.病毒表面具有血凝素-神经氨酸酶(HN)和融合(F)蛋白,它们在感染过程中起着至关重要的作用.研究发现,强毒株F蛋白在裂解位点附近有两对成双存在的碱性氨基酸赖氨酸(Lys)或精氨酸(Arg),而弱毒株在相应位置只有两个单个存在的碱性氨基酸.

sets of PCR primers were designed to amplify specific DNA fragment from the genomes of APMV- 1 ,DPV and GPV respectively for the diagnosis of the most common viral diseases in geese.The specific PCR productswere amplified by the corresponding primersfrom the reference strainsof each virus, but not from other pathogens;38field samples from different areas of Guangxi were detected with the developed PCR- based diagnosis protocol and 66. 6% ,5 5 . 6% and 75 % of the detected samples were positive for DPV,APMV- 1 and GPV respectively,and totally 42 . 8% ( 9/ 2 1 ) for the dual and triple infections.The results demonstrated that developed PCR- based protocols is a rapid,sensitive,specific and reliable for the diagnosis of these diseases in geese and can be applied in the field especially for the multiple infections and the epidemiological survey.

鸡最常见的肿瘤病为马立克氏病(MD)、禽白血病(AL)和网状内皮增生症(RE),它们可引起在临床上相似的组织器官肿瘤病变以及免疫抑制状态, 而且常常混合感染,是目前严重危害我国养鸡业的一类重要疾病.建立一种能够快速鉴别诊断三种肿瘤病的方法,尤显必要.PCR作为一种体外扩增技术,已广泛应用于禽病的诊断.发展多重PCR诊断技术对于临床禽病的鉴别提供方便、可靠的诊断具有重要的实用价值.