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。     

猪瘟、猪口蹄疫、高致病性猪蓝耳病疫苗有效免疫试验初探

为推广猪瘟、猪口蹄疫和高致病性猪蓝耳病3种疫苗有效免疫,在前期开展"猪瘟疫苗(脾淋源)、猪O型口蹄疫疫苗和高致病性猪蓝耳病疫苗有效免疫试验"确定新的免疫程序基础上进行扩大试验,进一步验证猪瘟疫苗1头份免疫剂量足以产生可靠的免疫保护;先免疫接种猪瘟疫苗,1周后免疫接种口蹄疫和高致病性猪蓝耳病疫苗,二者有明显的协同促进作用,适宜在农村散户中使用;3种疫苗同时分点注射,相互之间干扰较大,猪瘟病毒抗体产生时间推迟,不宜推广使用。     

牛O型、亚洲Ⅰ型口蹄疫疫苗不同免疫次数免疫后群体抗体合格率比较

本研究选取沈阳地区饲养管理正规的牛规模场,采用液相阻断ELISA试验方法测定牛血清样品中O型-亚洲Ⅰ型口蹄疫抗体水平,并计算免疫抗体的群体合格率。用O型-亚洲Ⅰ型二价苗一免、二免、三免的牛在免后28d时牛O型-亚洲Ⅰ型口蹄疫免疫抗体群体合格率研究结果表明,O型口蹄疫免疫抗体群体合格率分别为82.5%、100%、100%;亚洲Ⅰ型口蹄疫免疫抗体群体合格率分别为57.5%、97.5%、97.5%。一免后O型和亚洲Ⅰ型口蹄疫免疫抗体群体合格率下降速度均较快,一免后60dO型免疫抗体群体合格率降到72.5%,免后80d时O型、亚洲Ⅰ型口蹄疫免疫抗体群体合格率分别降为47.5%、12.5%。二免以上的牛口蹄免疫抗体群体合格率在28～120d内均较一免组高,而且抗体持续时间也长,三免后120d时O型、亚洲Ⅰ型口蹄疫免疫抗体群体合格率仍高达77.5%、75%。     

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。     

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。     

肉牛口蹄疫免疫抗体、3ABC抗体、RT-PCR核酸检测结果分析

[目的]为了掌握肉牛口蹄疫免疫抗体检测结果、口蹄疫非结构蛋白3ABC抗体检测结果、口蹄疫O-P液RT-PCR核酸检测结果三者的相关性,[方法]张掖市动物疫病预防控制中心对甘州区28头肉牛开展相关检测。[结果]检测结果表明:O型口蹄疫免疫抗体合格率28份,合格率100%,3ABC抗体阳性27份,阳性率96.4%;对3ABC抗体阳性的27头牛分2次进行实时荧光RT-PCR核酸检测,被检的27头牛均为阴性。     

不同免疫方式对仔猪免疫高致病性猪繁殖与呼吸综合征、猪瘟、猪口蹄疫三种疫苗抗体水平的影响

采用不同的免疫方式,对38头36~38日龄健康仔猪进行高致病性猪繁殖与呼吸综合征、猪瘟、猪口蹄疫3种疫苗进行免疫,分别于免疫前（0 d）和免疫后15、30、45、60、90 d采血进行这3种疫病抗体检测。结果发现效果最好的方法是先免疫猪瘟和口蹄疫疫苗14 d后再免疫高致病性猪繁殖与呼吸综合征疫苗;其次是猪瘟疫苗和高致病性猪繁殖与呼吸综合征疫苗分别释稀后混合为1针,口蹄疫疫苗另作1针同时分点注射;免疫效果最差的是高致病性猪繁殖与呼吸综合征、猪瘟、猪口蹄疫3种疫苗同时分3点注射。     

Antibody Responses Against Equine Influenza Virus Induced by Concurrent and by Consecutive Use of an Inactivated Equine Influenza Virus Vaccine and a Modified Live Equine Herpesvirus Type 1 Vaccine in Thoroughbred Racehorses

An inactivated equine influenza virus (EIV) vaccine and a live equine herpesvirus type 1 (EHV-1) vaccine are usually administered concurrently to Thoroughbred racehorses in Japan. The objective of this study was to evaluate whether concurrent administration of an inactivated EIV vaccine and a live EHV-1 vaccine in Thoroughbred racehorses influences the antibody response against EIV. We compared the antibody response against EIV in horses administered both vaccines on the same day (Group A; n = 27) and the response in horses administered an inactivated EIV vaccine first and then a live EHV-1 vaccine 1–2 weeks later (Group B; n = 20). In both groups, geometric mean hemagglutination inhibition (HI) titers against A/equine/Ibaraki/1/2007 and A/equine/Yokohama/aq13/2010 increased significantly after EIV vaccination. However, the percentage of horses that showed a twofold increase or greater in HI titers against A/equine/Yokohama/aq13/2010 was significantly higher in Group B (75%) than in Group A (37%; P = .02). These results suggest that the concurrent use of an inactivated EIV vaccine and a live EHV-1 vaccine reduced the immune response against EIV to some extent, and it would be better to use these vaccines consecutively, especially for naïve horses or horses whose vaccination history is incomplete.     

Immunization of cattle against Aujeszky's disease with inactivated adjuvant vaccine

The experiments with sheep and young cattle were carried out to test the immunizing efficacy of inactivated adjuvant vaccine against Aujeszky's disease. The vaccine application at doses of 1 ml and 2 ml to lambs at the age of eight to ten months caused the neutralizing antibody production with a significant rise of titres after revaccination. A survival of infection induced with a dose of 10(5.5) TKID50 of virulent virus was recorded in 62.5% of once vaccinated animals and in 87.5% of twice vaccinated animals. When applying different doses of vaccines (from 1 to 10 ml) to young cattle, the antibody reaction level was directly dependent on the inoculum quantity. The double inoculation of animals with vaccines of 2 ml and 5 ml caused the neutralizing antibody production at titres of 1:35, or 1:46. The animals, immunized with the live or inactivated IBR-vaccine possessing high antibody titres against IBR-virus, reacted upon the vaccination with inactivated Aujeszky's vaccine anamnestically, by early production of antibodies in high titres. Metaphylactic vaccination (2 ml of vaccine) of cattle in herds with an acute course days, however earlier during five days from the revaccination when it was carried out in seven days following the first vaccination.     

元江县2018-2021年生猪O型口蹄疫免疫效果评价与分析

为了解元江县生猪O型口蹄疫（FMD O）疫苗免疫状况,并评估免疫效果,2018-2021年在全县10个乡镇的规模场和散养户中,随机采集生猪血清样品,采用ELISA方法进行免疫抗体检测。结果显示：不同年份FMD O免疫抗体合格率平均为64.94%;不同区域FMD O免疫抗体合格率平均为64.01%;不同养殖方式规模场FMD O的免疫抗体合格率（66.23%）与散养户（64.61%）相比,相差1.62个百分点,差异不显著（P＞0.05）。结果表明,近年来元江县生猪FMD O整体免疫效果不是很理想,出现免疫不达标的年份、区域及养殖方式,应引起高度重视,检测结果可为元江县生猪FMD O的潜在风险点控制、疫苗选择及防控提供参考。     

Saponin Adjuvants. IV. Evaluation of The Adjuvant Quil a in the Vaccination of Cattle Against Foot-And-Mouth Disease

The saponin adjuvant Quil A has been investigated in the vaccination of cattle against foot-and-mouth disease. Using a Frenkel type vaccine a dose-response relationship has been established between Quil A and neutralizing antibody titres. Ten ml of vaccine was combined with 0, 50, 200, 800, and 3200 µg of Quil A. The combinations were each injected into 4 animals. The local reaction on the site of injection produced by injection of the vaccine alone and in combination with different doses of Quil A has been estimated. On this basis a therapeutical dose at 1 mg of Quil A has been estimated to combine maximum adjuvant effect with a minimum of adverse reactions. This dose has been tested in the vaccination of cattle with FMD vaccines derived from BHK suspension cell virus of type O and A respectively. The vaccines were tested in 10 ml and 5 ml doses with or without Quil A, and each in 4 animals. It is concluded that Quil A is a valuable adjuvant for use in the induction of neutralizing antibodies against foot-and-mouth disease in cattle.     

兔出血症-巴氏杆菌病二联灭活苗的研制

筛选出了具有良好免疫原性的兔瘟强毒株GMH881和兔巴氏杆菌C51-17株,研制出了兔出血症-巴氏杆菌二联灭活苗,对疫苗进行了免疫剂量、免疫产生期、兔出血症抗体测定、免疫保护期、保存期等试验：确定出二联苗免疫剂量1.0 mL;二联苗在免疫后5 d对兔病毒性出血症强毒的保护率达到100%,二联苗免疫后7d对兔巴氏杆菌的保护率均达到80%以上;二联苗的兔病毒性出血症抗体测定,结果表明,二联苗免疫家兔后7d HI抗体均可达22.75,15 d明显上升,二联苗HI效价30 d达到最高峰,可达28.0,二联苗在60~120 d均可维持在27.0~25.5水平,到180 d时抗体水平面略有下降为25.25,二联苗分别在免疫后4个月、6个月用兔出血症强毒攻击均产生100%保护,在6个月用2个MLD的兔巴氏杆菌攻击保护率可达70%以上,二联苗4~8℃条件下保存期暂定为1年,25℃条件下暂定为半年。     

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。     

Presence of antibodies to non-structural proteins of foot-and-mouth disease virus in repeatedly vaccinated cattle

For the purpose of removing infected animals by detecting humoral immune responses to non-structural proteins of the foot-and-mouth disease (FMD) virus, antibodies induced by contaminated residual non-structural proteins contained in less pure FMD vaccine can be problematic for serological screening. The aim of the present study was to measure the possible presence of antibodies against these non-structural proteins in repeatedly vaccinated calves and beef cattle. Five imported FMD vaccines were examined using two commercial ELISA kits, UBI FMDV NS EIA and Ceditest FMDV-NS, for serological testing. After five doses of vaccination, the serum of one calf tested positive, and two vaccines induced a significant increase in anti-3ABC antibodies in calves. This finding demonstrated that a positive reaction to non-structural proteins due to impurities in the FMD vaccine was detectable using commercial tests. A low percentage of field sera sampled from beef cattle in Kinmen also tested positive, but the key factor resulting in the positive reactions could not be positively identified based on our data.     

羊口蹄疫O型-亚洲1型二价灭活疫苗免疫后O型抗体水平的检测

为了探讨口蹄疫O型-亚洲1型二价灭活苗免疫接种羊后产生的O型抗体效价,采用不同免疫剂量和不同免疫时间免疫接种羊,应用正向间接血凝试验(IHA),检测其抗体消长规律.结果表明,羔羊母源抗体水平及维持时间与母羊抗体水平呈正相关,有效保护抗体能维持70 d左右;首免每只1 mL、2 mL同时免疫的4组间免疫抗体水平经方差分析差异不显著,首免不能产生有效的保护抗体水平;二免2 mL、2.5 mL不同时间免疫的4组,首免后15 d与首免后28 d进行二免产生的抗体经t检验差异极显著(P<0.01),首免后28 d二免的不同剂量组经方差分析差异不显著,有效抗体能维持约170 d,首免后15 d二免的免疫抗体水平最低;每只三免2 mL、3 mL的2个剂量组产生的有效抗体均能维持180 d,两组抗体经t检验差异不显著(P>0.05).     

复方中药偶蹄康对奶牛口蹄疫疫苗抗体水平、血清细胞因子及生化指标的影响

为研究复方中药偶蹄康对奶牛口蹄疫O型、A型、亚洲Ⅰ型3个血清型疫苗抗体水平、10种血清细胞因子含量及生化指标的影响,本试验将健康成年奶牛分为药物组和空白对照组,每组100头,连续拌料给药7 d后注射口蹄疫三联苗,注射疫苗后0、14、28、56 d分别采血,检测血清疫苗效价、血清细胞因子含量及生化指标。结果显示,注射疫苗后0、28和56 d药物组与空白对照组抗体效价无显著差异（P>0.05）;注射疫苗后14 d药物对口蹄疫3种血清型抗体效价的提升作用均极显著（P<0.01）。药物组血清总胆红素（T-Bil）降低,0、28 d差异显著（P<0.05）,56 d差异极显著（P<0.01）;28、56 d药物组与空白对照组葡萄糖含量差异显著（P<0.05）;0 d血磷含量差异极显著（P<0.01）,但未超出正常生理值范围,且后续检测无显著差异（P>0.05）。注射疫苗后14 d药物组血清CD4含量显著高于空白对照组（P<0.05）;注射疫苗后28 d药物组血清CD4、IL-2、IL-6、IL-10、IL-12、IL-18、IFN-γ含量极显著高于空白对照组（P<0.01）;注射疫苗后56 d药物组血清IL-6、IL-12含量极显著高于空白对照组（P<0.01）,CD4、IL-2、IL-4、、IL-18含量显著高于空白对照组（P<0.05）。综上可知,偶蹄康对奶牛口蹄疫O型、A型、亚洲Ⅰ型3个血清型疫苗效价有显著提升,对奶牛肝脏和肾脏功能无明显的损伤,且有一定的利胆作用,对奶牛细胞免疫和体液免疫机能有明显的提升作用。     

Early antibody responses of cattle for foot-and-mouth disease quadrivalent double oil emulsion vaccine

Foot-and-mouth disease (FMD) is an economically important disease of cloven-hoofed animals. The multiplicity of FMDV serotypes in animals poses a central problem in the policy of vaccination and is of much concern to health authorities. Hence it is the practice of vaccination with polyvalent vaccine for prophylactic measure. In the present report, we analysed the early antibody responses elicited by FMDV quadrivalent (FMDV O, A, C and Asia 1 serotypes) double emulsion (Montanide ISA 206) vaccines in cattle. We observed variations between various viral serotypes in eliciting early antibody response although neutralizing antibody response against all the four serotypes were detected as early as fourth day following vaccination. The duration of immunity also appeared to maintain for long period. The neutralizing antibody titres were maintained well above 2log(10) even after 6 months of vaccination irrespective of serotypes. Thus, allows the possibilities of two vaccinations per year for the maintenance of herd immunity.     

Comparison of sensitivity and specificity in three commercial foot-and-mouth disease virus non-structural protein ELISA kits with swine sera in Taiwan

Three commercialized ELISA kits for the detection of antibodies to the non-structural proteins (NSPs) of FMD virus were compared, using sera from uninfected, vaccinated, challenged and naturally infected pigs. The kinetics of the antibody response to NSPs was compared on sequential serum samples in swine from challenge studies and outbreaks. The results showed that ELISA A (UBI) and ELISA B (CEDI) had better sensitivity than that of the 3ABC recombinant protein-based ELISA C (Chekit). The peak for detection of antibodies to NSPs in ELISA C was significantly delayed in sera from natural infection and challenged swine as compared to the ELISA A and B. The sensitivity of the three ELISAs gradually declined during the 6-month post-infection as antibodies to NSP decline. ELISA kits A and B detected NSP antibody in 50% of challenged pigs by the 9-10th-day and 7-8th-day post-challenge, respectively. ELISA B and C had better specificity than ELISA A on sequential serum samples obtained from swine immunized with a type O FMD vaccine commercially available in Taiwan. Antibody to NSPs before vaccination was not detected in swine not exposed to FMD virus, however, antibody to NSPs was found in sera of some pigs after vaccination. All assays had significantly lower specificity when testing sera from repeatedly vaccinated sows and finishers in 1997 that were tested after the 1997 FMD outbreak. However, when testing sera from repeatedly vaccinated sows or finishers in 2003-2004, the specificity for ELISAs A, B and C were significantly better than those in 1997. This effect was less marked for ELISA A. The ELISA B was the best test in terms of the highest sensitivity and specificity and the lowest reactivity with residual NSP in vaccinates.     

Effectiveness of vaccines and vaccination programs for the control of foot-and-mouth disease in Uganda, 2001–2010

Foot-and-mouth disease (FMD) is a highly contagious disease of cloven-hoofed animals. In Uganda, FMD outbreaks are mainly controlled by ring vaccination and restriction of animal movements. Vaccination stimulates immunity and prevents animals from developing clinical signs which include lameness, inappetence, and decreased production. Ring vaccination and restriction of animal movements have, however, not successfully controlled FMD in Uganda and outbreaks reoccur annually. The objective of this study was to review the use of FMD virus (FMDV) vaccines and assess the effectiveness of vaccination programs for controlling FMD in Uganda (2001–2010), using retrospective data. FMD vaccine distribution patterns in Uganda (2001–2010) matched occurrence of outbreaks with districts reporting the highest number of outbreaks also receiving the largest quantity of vaccines. This was possibly due to “fire brigade” response of vaccinating animals after outbreaks have been reported. On average, only 10.3 % of cattle within districts that reported outbreaks during the study period were vaccinated. The average minimum time between onset of outbreaks and vaccination was 7.5 weeks, while the annual cost of FMDV vaccines used ranged from US $58,000 to 1,088,820. Between 2001 and 2010, serotyping of FMD virus was done in only 9/121 FMD outbreaks, and there is no evidence that vaccine matching or vaccine potency tests have been done in Uganda. The probability of FMDV vaccine and outbreak mismatch, the delayed response to outbreaks through vaccination, and the high costs associated with importation of FMDV vaccines could be reduced if virus serotyping and subtyping as well as vaccine matching were regularly done, and the results were considered for vaccine manufacture.     

Antibody responses of guinea-pigs, rabbits and pigs to inactivated porcine parvovirus vaccines

Antibody responses were compared in guinea-pigs, rabbits and pigs following vaccination with inactivated porcine parvovirus (PPV) vaccines. Mean PPV hemagglutination inhibition (HI) antibody titers of 52, 56 and 36 at 1 week after first vaccination and 896, 640 and 512 at 2 weeks after second vaccination were detected in guinea-pigs, rabbits and pigs, respectively. PPV vaccines prepared with greater concentrations of virus, as determined by hemagglutination (HA) units, and of aluminum hydroxide gel adjuvant, induced higher HI antibody titers in guinea-pigs. Optimal concentrations for inducing consistently high antibody titers consisted of vaccine virus with a HA titer of 256/0.1 ml and gel adjuvant at a final concentration of 50%. A second vaccination at 4 weeks compared to 2 or 3 weeks after first vaccination resulted in higher mean HI titers. These data provide preliminary information on the use of guinea-pigs or rabbits as laboratory animal models for testing the potency of PPV vaccines.