开阳县中小规模养殖场口蹄疫监测分析

为了解开阳县中小规模养殖场的口蹄疫防控情况,采用ELISA试验对52个中小规模养殖场猪O型口蹄疫免疫抗体和口蹄疫非结构蛋白3-ABC抗体进行检测,检测出3-ABC抗体阳性病例进一步通过RT-PCR检测口蹄疫病毒确诊。结果:猪O型口蹄疫免疫抗体共检测1 684份,合格率88.3%(1 487/1 684);口蹄疫非结构蛋白3-ABC抗体共检测1 684份,3-ABC抗体阳性9份,阳性率0.53%(9/1 684),进一步通过RT-PCR检测口蹄疫病毒,结果为阴性。结果表明,开阳县中小规模养猪场的猪O型口蹄疫免疫抗体效价达到国家农业部标准,有良好的免疫保护效果,没有检测出口蹄疫病毒,口蹄疫的防控处于良好状态。     

安徽省2015年规模猪场高致病性蓝耳病定点监测与分析

[目的]掌握安徽省规模猪场高致病性蓝耳病的感染状况和免疫抗体水平。[方法]采用抗体阻断ELISA、荧光RT-PCR方法检测了24个猪场的588份血清样本和28个场点的790份组织样品。[结果]高致病性蓝耳病个体抗体免疫合格率为78.1%,群体免疫合格率为75.0%;中型猪场的平均免疫抗体合格率为87.1%、小型猪场为63.9%。高致病性蓝耳病病毒核酸个体阳性率为28.7%,群体阳性率为75.0%;中型猪场、小型猪场和生猪屠宰场的高致病性蓝耳病病毒核酸个体阳性率分别为41.7%、19.5%和6%。[结论]2015年安徽省规模猪场的高致病性蓝耳病抗体免疫合格率较高,但存在带毒现象,建议加强疫病的免疫和综合防控。     

2015—2018年安徽省定点猪场主要疫病病原和血清抗体监测

为全面掌握安徽省口蹄疫、猪瘟、高致病性猪繁殖与呼吸综合征和猪伪狂犬病等主要猪群疫病的感染及免疫状况,2015—2018年,从安徽省东部、中部和南部选取12个生猪养殖场,应用荧光定量RT-PCR和ELISA检测方法,连续4年对上述疫病病原和血清抗体进行检测。结果显示：每年均检测出口蹄疫3ABC阳性抗体,O型和A型口蹄疫免疫抗体合格率呈逐年下降趋势。猪瘟和高致病性猪繁殖与呼吸综合征免疫情况较好,抗体合格率均超过农业农村部规定的70%标准,高致病性猪繁殖与呼吸综合征病毒核酸阳性率呈逐年下降趋势。猪伪狂犬病在猪场中存在一定的流行,gE（野毒）抗体阳性率在0.74%~19.90%之间;gB免疫抗体合格率在35.64%~71.16%之间,合格率较低且呈逐年下降趋势。小型猪场的主要疫病免疫抗体合格率普遍低于中型猪场,保育猪群和育肥猪群抗体合格率低于其他生产阶段猪群。结果提示,该地定点猪场的口蹄疫和猪伪狂犬病防控效果不理想,不仅存在一定的病毒感染,免疫抗体合格率也偏低,病毒流行风险较高,需要加强监测和免疫;猪瘟、高致病性猪繁殖与呼吸综合征总体防控效果较好,但需要加强种公猪免疫。     

青海省民和县种羊场种公羊“两疫一病”的血清学调查

本文对民和县三个种羊场的小尾寒羊、陶赛特种公羊进行了口蹄疫、小反刍兽疫免疫抗体和布病检测,结果为:O型口蹄疫免疫抗体检测177份,检出阳性162份,群体合格率为91.5%;小反刍兽疫免疫抗体检测185份,检出阳性152份,群体合格率为82.6%;布病检测血样677份,未检出阳性;免疫抗体合格率达到农业农村部规定的≥70%以上,表明O型口蹄疫和小反刍兽疫的免疫抗体效果确实。     

祁连山北麓中部地区牦牛常见病的血清学调查

[目的]为了掌握祁连山北麓中部地区牦牛常见病的感染情况。[方法]对祁连山北麓中部地区的牦牛常见病开展了血清学检测。共检测280份血清样品,分别检测了布病、口蹄疫、牛传染性鼻气管炎、弓形虫、牛副结核病的感染抗体。[结果]检出布病阳性样品3份,平均阳性率1.2%;检出口蹄疫病毒非结构蛋白3ABC抗体阳性样品31份,平均阳性率11.1%;检出牛传染性鼻气管炎阳性样品14份,平均阳性率5.0%;检出弓形虫抗体阳性样品87份,平均阳性率31.1%;检出牛副结核抗体阳性样品1份,平均阳性率0.4%。[结论]通过血清学检测,初步掌握了5种疫病的感染情况,为科学防控提供了科学依据。     

2016年江苏省猪口蹄疫监测结果分析

为了解江苏省猪口蹄疫感染和免疫情况,采用荧光RT-PCR和ELISA方法,对收集的8000份猪组织样品和2718份猪血清样品分别进行口蹄疫病毒核酸和O型口蹄疫抗体检测.数据显示,口蹄疫病毒核酸阳性率为0;O型口蹄疫抗体合格率为68.95%.结果表明,江苏省规模场和屠宰场猪口蹄疫防控情况较好;O型口蹄疫抗体合格率略低于70%,说明仍有个别场户的口蹄疫免疫工作存在瑕疵.     

辽宁阜新地区猪牛羊口蹄疫免疫抗体监测

本研究对辽宁阜新地区春季集中免疫期间猪、牛、羊口蹄疫免疫抗体采用ELISA法进行监测,同时对猪、牛、羊进行口蹄疫病毒非结构蛋白抗体单抗阻断ELISA检测和口蹄疫病毒荧光RT-PCR检测,将免疫抗体监测与病毒检测结果进行综合系统分析,有效评估该地区口蹄疫预防免疫效果和感染带毒情况,及时掌握口蹄疫防控工作情况,做出风险评估,进行风险交流,发挥预警预报作用。结果表明,在口蹄疫春季集中免疫后,阜新地区猪、牛、羊O型口蹄疫平均免疫抗体合格率为86.97%,牛、羊亚洲Ⅰ型口蹄疫平均免疫抗体合格率为86.74%,奶牛A型口蹄疫平均免疫抗体合格率为95.62%,均超过了国家农业农村部对重大动物疫病评价的总体要求(有效免疫抗体合格率要达到70%以上)。     

内蒙古地区牛羊口蹄疫灭活疫苗的免疫效果比较研究

为准确掌握牛羊口蹄疫疫苗免疫效果,2012年对内蒙古自治区的牛羊口蹄疫O—AsiaI型双价灭活疫苗和牛羊口蹄疫A型灭活疫苗免疫效果进行了监测。采用液相阻断ELISA方法。共检测了8个旗县23018份免疫牛羊口蹄疫O—AsiaI型双价灭活疫苗和牛羊口蹄疫A型灭活疫苗15日、30日、60日的血清中口蹄疫免疫抗体水平。结果显示,牛羊口蹄疫疫苗免疫效果总体良好,免疫抗体合格率超过了70％。规模化奶牛养殖场免疫效果稳定,散养地区免疫效果稳定性差,且不同厂家的疫苗免疫效果不同,加强免疫后A、B、D三个厂家抗体合格率能达到100％,C厂家的免疫效果较差,抗体合格率为93-3％。采用3ABC—ELISA检测试剂盒对部分地区牛羊进行感染抗体检测,结果为阴性。     

宁夏固原市肉牛口蹄疫和布鲁氏菌病血清抗体检测与分析

[目的] 为了调查宁夏固原市肉牛口蹄疫和布鲁氏菌病的流行情况,[方法]通过采集74份不同月龄肉牛血清样本,采用酶联免疫吸附试验(ELISA)对2种疫病抗体进行检测和分析。[结果],抗体阳性率由高到低分别为A型口蹄疫(48.65%)、O型口蹄疫(43.24%)、布鲁氏菌病(12.16%)。混合抗体阳性率中主要以O型和A型口蹄疫混合抗体阳性率最高(58.54%)。O型口蹄疫在西吉县的阳性检出率最高(88.24%),彭阳县最低(6.67%);A型口蹄疫在西吉县阳性检出率最高(82.35%),彭阳县最低(26.67%);布鲁氏菌病在原州区阳性检出率最高(15.00%),泾源县和彭阳县未检出。从不同年龄来看,3种疫病均在＞12月龄的肉牛中阳性率最高,分别为O型口蹄疫69.23%、A型口蹄疫76.92%、布鲁氏菌病15.38%。[结论] 固原市各个县区肉牛养殖地区均出现2种病原感染的情况,以O型和A型口蹄疫混合感染为主。在肉母牛养殖过程中,应加强对以上病原的检疫并采取相应的防控措施。     

不同方法对夏南牛口蹄疫免疫抗体水平检测的比对试验

[目的]为探索中小规模养牛场自繁自育条件下,繁殖母牛(指经产1胎以上的母牛,下同)、断奶犊牛(指4月龄以上的犊牛,下同)口蹄疫适宜的免疫时间,检测口蹄疫免疫的效果,为中小规模养牛场制定科学的口蹄疫免疫程序提供参考数据,开展本试验。[方法]采用液相阻断ELISA、固相竞争ELISA两种检测方法进行比对试验。[结果]采用液相阻断ELISA试验结果显示:繁殖母牛抗体效价,在免疫后30 d,60 d,90 d和120 d时免疫抗体合格率分别为65.6%,87.5%,78.1%和46.8%;断奶犊牛在免疫后10 d,40 d,70 d,100 d时免疫抗体合格率分别为75%,100%,83.3%,41.6%。采用固相竞争ELISA试验结果显示:繁殖母牛抗体效价,在免疫后30 d,60 d,90 d,120 d时免疫抗体合格性率分别为78.1%,100%,100%,75%;断奶犊牛在免疫后10 d,40 d,70 d,100 d时免疫抗体合格率分别为83.3%,100%,100%,75%。[结论]从试验结果来看,固相竞争ELISA试验检测只能判定结果是抗体阳性、或抗体阴性,试验操作简单方便,结果判定也容易辨别,但与液相阻断ELISA试验结果相比,抗体水平检测有一定的误差。     

规模奶牛场O型口蹄疫疫苗抗体消长规律研究

[目的]通过免疫抗体监测,掌握其在奶牛体内消长规律;建立适合本区奶牛口蹄疫疫苗常规免疫程序,提高有效免疫保护;探索延平区内两个常用口蹄疫疫苗的抗体产生时间和免疫抗体持续时间,为有效科学免疫,预防口蹄疫疫情提供科学依据。[方法]血样采集使用一次性真空采血管,抗体检测采用液相阻断ELISA检测方法,抗体效价判定依据畜牧兽医主管部门动物疫病监测方案。[试验对象]选择福建省南平市延平区两个分别常年免疫政府采购疫苗（中牧实业）、自行采购疫苗（内蒙金宇）的A、B规模化牛场,各选取一定数量的初生犊牛（犊牛20 头及对应母牛20 头）。[结果]A场母牛产后、犊牛出生当天O型抗体合格率达100%,第四周达到峰值后开始下降,至12周抗体合格率降至50%,确定首免时间为犊牛出生后12 周,首免后第6周抗体合格率降至55%,确定二免时间为首免后第6周;B场母牛产后、犊牛出生当天O型抗体合格率达95%,第四周达到峰值后开始下降,至9周抗体合格率降至55%,确定首免时间为犊牛出生后9 周,首免后第3周抗体合格率降至28%,确定二免时间为首免后第3周。[结论]根据监测试验结果,A场的免疫程序设计为犊牛出生后12 周开始首免,首免后第6周开始2 免,以后每4 个月免疫1 次;B场的免疫程序设计为犊牛出生后9 周开始首免,首免后第3 周开始2 免,以后每4 个月免疫1 次。     

2014-2020年张掖市牛口蹄疫免疫抗体监测分析

[目的]为了及时掌握牛口蹄疫免疫后的免疫效果,为口蹄疫防控提供理论依据.[方法]张掖市动物疫病预防控制中心每年春秋两季集中免疫后对全市6县(区)送检的牛口蹄疫免疫血清开展了免疫抗体检测,为科学评价免疫效果提供了理论依据.[结果]2014-2020年,共检测牛O型口蹄疫免疫血清12 328份,抗体合格10 910份,平均...     

武威市肉牛口蹄疫三价苗抗体水平 评估研究

本实验从甘肃省武威市4个县区（凉州区、古浪县、天祝县、民勤县）采集的320份牛血清样品效价进行了检测。中O型抗体检测免疫合格率分别是71.00%,86.30%,80.00%,91.30%,平均合格率为82.15%。检测出亚洲Ⅰ型抗体免疫合格率82.30%,76.30%,70.00%81.30%,平均合格率为77.23%;检测出A型抗体免疫合格率87.75%,93.50%67.30%,76.30%,平均合格率为81.50%。四县区散户肉牛血清样品中O型抗体检测免疫合格率分别：58.80%,61.30%,63.80%,86.30%,平均合格率为67.55%;检测出亚洲Ⅰ型抗体免疫合格率81.00%,75.00%,71.30%,78.80%,平均合格率为76.30%;检测出A型抗体免疫合格率71.00%,77.50%,83.80%,85.00%,平均合格率为79.00%。通过检测结果可以发现武威市肉牛口蹄疫三价苗抗体合格率高于70%,且武威市规模养殖场肉牛口蹄疫三价苗抗体检测合格率高于散养牛的。     

Development and validation of a 3ABC indirect ELISA for differentiation of foot-and-mouth disease virus infected from vaccinated animals

Non-structural protein (NSP) 3ABC antibody is considered to be the most reliable indicator of present or past infection with foot-and-mouth disease virus (FMDV) in vaccinated animals. An indirect ELISA was established, using purified His-tagged 3ABC fusion protein as antigen, for detection of the antibody response to FMDV NSP 3ABC in different animal species. The method was validated by simultaneous detection of the early antibody responses to NSP and structural protein (SP) in FMDV Asia 1 infected animals. The performance of the method was also validated by detection of antibody in reference sera from the FMD World Reference Laboratory (WRL) in Pirbright, UK, and comparison with two commercial NSP ELISA kits. The results showed that the antibody response to SP developed more quickly than that to NSP 3ABC in FMDV infected animals. In contact-infected cattle, the antibody response to NSP 3ABC was significantly delayed compared with that to SP antibody. The early antibody responses to SP and NSP 3ABC in FMDV inoculated cattle and contact-infected or inoculated sheep and pigs were generally consistent. In pigs, 3ABC antibody was linked to the presence of clinical signs; however, in sheep, subclinical infection was detected by the development of 3ABC antibodies. Therefore, the antibody responses to 3ABC varied between host species. Eight out of 10 positive serum samples from FMD WRL were tested to be positive at cutoff value of 0.2. The rate of agreement with the ceditest FMDV-NS and the UBI NSP ELISA were 98.05% (302/308) and 93.2% (287/308), respectively. The prevalence of 3ABC antibodies reached 71.4% in some diseased cattle herds. The further work is required to evaluation the performance of this method in different animal species and different field situations.     

间接血凝试验在家畜口蹄疫免疫抗体检测中的应用

为了节省IHA（间接血凝试验）血凝抗原,扩大家畜O型口蹄疫免疫抗体检测数量,在不影响检测效果（合格率）的基础上,探索和改进原正向间接血凝试验检测方法。试验分别用口蹄疫O型-Asia 1型二价灭活苗和猪O型口蹄疫苗对天水地区几个养殖场的家畜进行了免疫注射,免疫后（牛免疫21 d、猪免疫28 d）随机抽样采血,常规分离血清,采用简化后的正向间接血凝试验进行牛和猪口蹄疫O型免疫抗体检测试验。结果表明：免疫合格率分别达到97.5%和92.5%;改进后的IHA既加快了操作速度、节省诊断抗原,又降低了检测成本。在家畜O型口蹄疫检测工作中具有推广应用价值。     

Immune Effect of Inactivated Vaccines against Foot-and-Mouth Disease and Their Interference on Differential Diagnosis

Vaccination with inactivated vaccine is an important measure to prevent and control foot-and-mouth disease (FMD), however, the immune effect and antigenic purity of inactivated vaccines are two major concerns for the establishment and evaluation of FMD free zones with vaccination. In this study, four groups of FMD type O and type A bivalent inactivated vaccines from 3 FMD vaccine manufacturers (designated as A, B and C) were selected to inoculate healthy juvenile cattle of FMD free. All cattle were immunized 3 or 4 times at a 1-month interval. Serum samples were collected before and after 1 month of every vaccination to determine the level of antibody to structural protein and non-structural protein. Results：(1) The qualified rates of antibody to structural protein: in group a1 (vaccine from company A, different batches), the antibody qualified rate could reach 100% for type O and type A, respectively after each vaccination. In group a2 (vaccines from company A, same batch), the antibody qualified rates were 36.7%, 98.3% and 100% for type O, and 15%, 86.7% and 100% for type A after the first to the third vaccination, respectively. In group b (vaccine from company B, same batch), the antibody qualified rates were 18.3%, 97% and 100% for type O, and 1.7%, 45% and 53.3% for type A after the first to the third vaccination, respectively. In group c (vaccines from company C, same batch), the antibody qualified rates were 26.7%, 96.7% and 100% for type O, and 21.7%, 71.7% and 100% for type A after the first to the third vaccination, respectively. (2) Antibody positive rate to non-structural protein 3ABC (confirmed with second ELISA test): In group a1, the positive rates were 0.7%, 1.4%, 9.5% and 4.8% after the first to the fourth vaccination, respectively; In group a2 and c, no 3ABC antibody-positive animal was detected after 3 repeated vaccination; In Group b, only one animal with a positive rate of 0.6% was detected after the third vaccination. The antibody qualified rates to the structural protein of FMDV in 3 of the 4 groups were far less than 70% after the primary vaccination, however, those were increased significantly after boost and repeated vaccination. The antigen purity of vaccines in three groups (a2, b and c) can meet the requirement of OIE standard on the FMD vaccine, however, the seroconversion to 3ABC antibody was obvious in animals from group a1 after repeated vaccination, which would cause some extent of interference to differential diagnosis. Also, a combination of a primary screening test and a confirmatory ELISA test can further improve the accuracy of differential diagnosis. This study provides an important scientific basis to make a rational program for establishment and evaluation of FMD free zone with vaccination.     

口蹄疫灭活疫苗的免疫效果及其对鉴别诊断的干扰

灭活疫苗免疫是防控口蹄疫的重要措施,但是灭活疫苗的免疫效果及其对感染与免疫鉴别诊断的干扰一直是口蹄疫免疫无疫区建设评估需要明确的重要问题。本研究中选择了3个企业（代号A、B与C）的4组口蹄疫O型与A型二价灭活疫苗,分别免疫口蹄疫抗体阴性健康未成年牛,免疫3～4次,测定免疫前后结构蛋白和非结构蛋白抗体的应答水平。结果显示：（1）结构蛋白抗体合格率：a1组（A企业多批次疫苗）4次免疫后O型和A型均为100%;a2组（A企业同批次疫苗）一~三免O型为36.7%、98.3%与100%,A型为15%、86.7%与100%;b组（B企业疫苗）一~三免O型为18.3%、97%与100%,A型为1.7%、45%与53.3%;c组（C企业疫苗）一~三免O型为26.7%、96.7%与100%,A型为21.7%、71.7%与100%。（2）非结构蛋白3ABC抗体阳性率（两种方法复核结果）：a1组一~四免分别为0.7%、1.4%、9.5%与4.8%;a2组和c组三次免疫均未检测到阳性;b组仅三免后阳性率为0.6%。3组灭活疫苗首次免疫牛的抗体合格率远不及70%,但加强免疫后抗体合格率均显著提高;非结构蛋白抗体检测结果表明有3组疫苗的抗原纯净度符合OIE的要求,但a1组灭活疫苗免疫后,仍然对感染与免疫鉴别诊断存在干扰;采用两种非结构蛋白抗体检测方法进行复核检验,可以提高感染与免疫鉴别诊断的准确性。本研究为口蹄疫免疫无疫评价方案的制定提供了科学依据。     

甘肃省牛、羊FMD亚洲Ⅰ型和O型免疫抗体水平调查与分析

采用IHA和LB-ELISA,对检测来自全省14个州市36个规模场和228个散养户的1212份牛和羊血清进行O型和Asia-Ⅰ型FMD免疫抗体检测.O型FMD检测牛647份,免疫合格559份,平均合格率为86.39%,滴度大于1:128有399份;检测羊675份,免疫合格569份,平均合格率为84.29%,滴度大于1:...     

云南省牛病毒性腹泻-黏膜病血清流行病学调查

[目的]牛病毒性腹泻—黏膜病(bovine viral diarrhea-mucosal disease, BVD)引起牛腹泻、呼吸系统疾病、生殖功能障碍、免疫抑制、母畜流产、死胎等,对牛产业发展危害严重。牛病毒性腹泻—黏膜病病毒(bovine viral diarrhea-mucosal disease virus, BVDV)在我国大部分牛群中普遍存在,各地流行情况严重程度不同,本调查旨在调查云南省BVDV的流行情况。[方法]调查通过采用商品化的酶联免疫吸附试验(ELISA)试剂盒对BVDV感染和流行情况进行调查,采集了云南省4个州10个县(市)的部分规模牛场及散养户的牛血清样品456份。[结果]结果发现,云南省不同地区所检的牛血清样品总抗体阳性率为16.45%(75/456),抗原阳性率为0.53%(2/378),其中抗体阳性率以大理州洱源县60.0%(9/15)最高,而丽江市华坪县的血清样品中未检测到抗体阳性,大理州宾川县和丽江市宁蒗县的抗原阳性率较低,分别为7.69%(1/13)和4.00%(1/25)。云南省规模场牛的血清样品抗体总阳性率为27.27%(45/165),抗原阳性率为1.15%(1/87),散养户牛的分别为10.31%(30/291)和0.34%(1/291)。[结论]云南省的牛群中存在着BVDV感染的情况,其抗体抗原的阳性率水平跟地区有着紧密的联系,不同的养殖方式抗原抗体水平存在着一定差异,必须要加强云南省BVDV监测与防控,减少其造成的经济损失。