4个厂家不同批次猪瘟疫苗免疫效果比较试验

在同一条件下对4个厂家生产的8个批次的猪瘟原代细胞苗进行了免疫效果评价试验,并与猪瘟传代细胞苗免疫效果进行比较。结果发现4个厂家生产的猪瘟原代细胞苗二次免疫效果较好,但部分厂家存在批间差异、质量不稳定现象。猪瘟传代细胞苗免疫效果优于猪瘟原代细胞苗。     

猪瘟脾淋苗和传代细胞苗田间免疫效果比较试验

为比较猪瘟脾淋苗和传代细胞苗的免疫效果,在厦门市同安区某规模猪场,选用代号为CQ、CD和JX 3个厂家生产的猪瘟脾淋苗和传代细胞苗进行免疫效果试验。随机选取45头30日龄断乳仔猪,分为3组,30日龄首免,首免后28 d二免,A组免疫接种CQ厂家的猪瘟脾淋苗,B组免疫接种CD厂家的猪瘟脾淋苗,C组免疫接种JX厂家的猪瘟细胞传代苗,通过定期跟踪3组猪群血清中的抗体水平,评估疫苗的免疫效果。结果显示:3组猪群二免后7 d前免疫抗体抗体水平和阳性率无显著差异,38 d后才出现免疫抗体水平和阳性率显著差异,以C组猪群的抗体阳性率最高,A组猪群的抗体阳性率最低。     

不同RID猪瘟兔化弱毒细胞苗免疫效果评价

为了比较不同兔体感染剂量(RID)的猪瘟兔化弱毒细胞苗的免疫效果,试验在市场上随机选取A、B两厂家生产的猪瘟兔化弱毒细胞苗(A厂家原代细胞苗12 000 RID、B厂家传代细胞苗30 000 RID)对四川省内江市某种猪场提供的186头20日龄健康仔猪进行免疫,将186头仔猪随机分为6组,每组31头,分别于20日龄、60日龄使用1,2,4头份三个剂量进行首免及加强免疫,并分别于免疫前(20日龄)、50日龄、100日龄采血分离血清,用猪瘟间接酶联免疫吸附试验(ELISA)测定抗体水平。结果表明:以1头份(30 000 RID)B厂家生产的猪瘟传代细胞苗免疫效果最好,其次是A厂家生产的4头份(48 000 RID)原代细胞苗,而1头份(12 000 RID)免疫效果较差。说明猪瘟兔化弱毒细胞苗RID含量在30 000~60 000 RID时免疫效果较好。     

猪瘟强化免疫措施

<正>1技术措施1.1疫苗选用可选用质量好,不易被外源病毒污染的猪瘟活疫苗(传代细胞源),即猪瘟ST苗进行免疫。该苗采用了进口克隆同源细胞,避免了使用和培养异源细胞(如牛睾丸细胞)易被外源病毒污染的缺陷。该疫苗病毒滴度高,可达牛睾丸细胞苗的10倍以上,成品苗RID(即疫苗感染量或反应量)可达15000个以上,由于RID含量高,可控制猪瘟亚临床感染,故该苗对体内有一定母源抗体和免疫抗体的猪的免疫效果也较     

猪瘟疫苗田间免疫效果监测

为准确掌握猪瘟疫苗免疫效果,2010-2012年对投放安徽省的猪瘟疫苗免疫效果进行了监测。采用抗体阻断ELISA方法,检测了454个猪场7439份免疫猪瘟弱毒活疫苗1个月左右的血清中猪瘟免疫抗体水平。结果显示,安徽省猪瘟疫苗免疫效果总体良好,免疫抗体合格率超过了70％：脾淋组织苗和细胞苗免疫效果相当,但脾淋组织苗免疫效果稳定,细胞苗免疫效果稳定性较差：不同厂家疫苗免疫效果参差不齐。     

猪瘟活疫苗(传代细胞源)免疫产生期和免疫持续期试验

将三批猪瘟活疫苗(传代细胞源)以单剂量分别接种仔猪进行免疫产生期试验。在免疫同时以及免后1、2、3、4、5日连同对照组分别攻击猪瘟强毒,攻毒后观察16天,结果表明,猪瘟活疫苗(传代细胞源)免后4日即可产生坚强的免疫保护力。将三批猪瘟活疫苗(传代细胞源)以单剂量分别接种仔猪进行免疫持续期试验。在免后3个月、6个月、9个月、12个月、15个月连同对照组分别攻击猪瘟强毒,攻毒后观察16天,结果表明,猪瘟活疫苗(传代细胞源)的免疫持续期可长达15个月。     

STK猪瘟活疫苗与ST细胞苗及脾淋组织苗免疫效果试验

将STK猪瘟活疫苗、ST猪瘟活疫苗、猪瘟脾淋组织苗和生理盐水(对照组)分别接种CSFV血清学阴性(CSFV抗体阻断率≤30%)的断奶仔猪,用美国IDEXX公司的猪瘟抗体检测试剂盒检测其抗体水平的动态变化差异,并分析抗体合格率(或阳性率)、阻断率等指标。结果表明:仔猪二次免疫STK猪瘟活疫苗后25天(即90日龄),猪瘟抗体的合格率达到100%,其中85%仔猪的抗体水平达到了比较高的滴度(阻断率≥60%),且二次免疫后在整个生长期都能维持较高的抗体水平。免疫ST猪瘟活疫苗及猪瘟脾淋组织苗后,在90日龄猪瘟抗体的合格率虽能达到或接近100%,但抗体水平处于高滴度的比例不大:ST细胞苗40%仔猪抗体阻断率≥60%,脾淋苗只有35%仔猪抗体阻断率≥60%,均低于免疫STK猪瘟活疫苗的抗体水平,且较高抗体水平维持的时间短于STK猪瘟活疫苗。各项结果表明,STK猪瘟活疫苗对仔猪有很好的免疫效果,能产生较高水平及较长时间的免疫保护力,且免疫效果优于ST猪瘟活疫苗和猪瘟脾淋组织苗。     

政府采购的猪瘟疫苗免疫效果和体会

<正>2011年至2014年,根据广西动物疫病预防控制中心的安排,每年我们都亲自用政府采购的猪瘟疫苗给6个~8个猪场(户)接种免疫,并检测免疫抗体,观察临床使用效果。共免疫检测了3个疫苗生产厂家生产的猪瘟疫苗,其中细胞源活苗2个,传代细胞源活苗1个。2014年还开展了4个不同厂家生产的猪瘟免疫抗体对比试验。现将免疫监测和临床观察过程以及分析结果报告如下。     

猪瘟传代细胞活疫苗、口蹄疫和高致病性猪蓝耳病联合免疫效果试验研究

<正>为评估猪瘟传代细胞活疫苗在猪瘟、高致病性猪蓝耳病和口蹄疫三种疫苗同步两点免疫新技术(即"321"免疫新技术)应用中的免疫效果,特进行本试验。1材料与方法1.1试验地点:富民县赤鹫镇大平地村委会、西山区海口镇双哨村委会。1.2试验动物:随机选取临床健康生猪,两县区各1000头,合计2000头。1.3疫苗选择:西山区:猪瘟传代细胞苗,高致病性猪蓝耳病活疫苗,猪口蹄疫合成肽疫苗。富民县:猪瘟传代细胞苗,高致病性猪蓝耳     

猪瘟脾淋苗与细胞苗免疫效果比较分析

为比较猪瘟脾淋苗和传代细胞苗的免疫效果,在陕西省汉中市某规模化养殖水平较高的猪场,选用编号为A的政府采购猪瘟脾淋苗和编号为B的某公司生产的猪瘟细胞苗,开展2种疫苗免疫效果比对试验。结果表明,2种疫苗免疫后都能刺激机体产生免疫应答反应,无论是标准剂量还是加大剂量,细胞苗的免疫效果都优于脾淋苗。此外,母源抗体和个体差异对疫苗免疫效果有一定影响。     

猪瘟猪伪狂犬病二联苗对仔猪免疫效果观察

本文探讨了猪瘟(CSF)、猪伪狂犬病(PR)活苗不同时间对仔猪免疫效果的相互影响。结果表明:同时免疫两种活疫苗(二联苗组),PR会干扰CSF前期抗体的产生。二联苗组猪瘟抗体3周后才达到阳性,而猪伪狂犬病抗体在7日时就达到阳性,两种抗体均在49日达到峰值,峰值均比单一免疫、分时免疫的峰值略低。分时免疫两种疫苗产生的抗体均比单一免疫时的抗体要低,且相互干扰不明显。     

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。     

Simultaneous vaccination of piglets against foot-and-mouth disease and classical swine fever

Six-week-old piglets, born of unvaccinated sows, were vaccinated against foot-and-mouth disease (FMD) with a trivalent, inactivated vaccine containing an adjuvant or vaccinated against classical swine fever (CSF) with a live attenuated vaccine or against both diseases simultaneously at two different sites. The antibody response to the FMD vaccine was not significantly influenced by the simultaneous vaccination against CSF. FMD vaccine administered simultaneously with the CSF vaccine produced a significantly higher antibody response to CSF than occurred with CSF vaccination only.     

Efficacy of swine influenza A virus vaccines against an H3N2 virus variant

We compared the efficacy of 3 commercial vaccines against swine influenza A virus (SIV) and an experimental homologous vaccine in young pigs that were subsequently challenged with a variant H3N2 SIV, A/Swine/Colorado/00294/2004, selected from a repository of serologically and genetically characterized H3N2 SIV isolates obtained from recent cases of swine respiratory disease. The experimental vaccine was prepared from the challenge virus. Four groups of 8 pigs each were vaccinated intramuscularly at both 4 and 6 wk of age with commercial or homologous vaccine. Two weeks after the 2nd vaccination, those 32 pigs and 8 nonvaccinated pigs were inoculated with the challenge virus by the deep intranasal route. Another 4 pigs served as nonvaccinated, nonchallenged controls. The serum antibody responses differed markedly between groups. After the 1st vaccination, the recipients of the homologous vaccine had hemagglutination inhibition (HI) titers of 1:640 to 1:2560 against the challenge (homologous) virus. In contrast, even after 2nd vaccination, the commercial-vaccine recipients had low titers or no detectable antibody against the challenge (heterologous) virus. After the 2nd vaccination, all the groups had high titers of antibody to the reference H3N2 virus A/Swine/Texas/4199-2/98. Vaccination reduced clinical signs and lung lesion scores; however, virus was isolated 1 to 5 d after challenge from the nasal swabs of most of the pigs vaccinated with a commercial product but from none of the pigs vaccinated with the experimental product. The efficacy of the commercial vaccines may need to be improved to provide sufficient protection against emerging H3N2 variants.     

Effect of route of vaccination on the prevention of infectious laryngotracheitis in commercial egg-laying chickens

Commercial egg-laying chickens were vaccinated for infectious laryngotracheitis (ILT) with one of five commercially available vaccines (designated A, B, C, D, and E) on five separate farms by either eyedrop (e), spray (s), or double dose in the water (w) method. Groups were identified by the vaccine designation and the method of vaccination. Birds from the test groups were transferred to an isolation facility and challenged intratracheally 3 wk after vaccination. The remaining birds were given a second vaccination with the original chicken embryo origin vaccine by spray or a chicken embryo origin vaccine if the first vaccine was of tissue culture origin. After challenge, birds were monitored for clinical signs. Those surviving were euthanatized on day 6 postchallenge, and tissues and blood were collected for histopathology, virus isolation, and serology. On the basis of histopathology and enzyme-linked immunosorbent assay (ELISA) results, after one vaccination, all chickens given vaccines by eyedrop were provided better protection than nonvaccinated controls (CTLs). Birds in groups Bs and Ds had lower microscopic lesion scores whereas only birds given Bs had higher ELISA titers than CTLs. Birds in groups As and Cs and groups Bw birds taken from the rear of the barn (r) had microscopic lesion scores that were no different from those of CTLs. These same birds in addition to vaccine Ds had ELISA titers no different from those of CTLs. Of all vaccines, only A given by eyedrop or spray produced higher virus isolation titers than those of CTLs. The remainder of the vaccines produced virus isolation titers that were no different from those of CTLs. After two vaccinations, all groups had lower microscopic lesion scores than CTLs. Only Bw birds from the middle of the barn Bs, EeDs, and AsAs had virus isolation results that were higher than those of CTLs. Only groups BwrBs, CsCs, and DsDs had ELISA titers no different from those of controls. These results suggest that a priming vaccination followed by a booster dose offers better protection against ILT than a single vaccination alone. Vaccine application by eyedrop provides more uniform protection if only one vaccination is given, whereas spray vaccination may serve as an alternative method of vaccination for birds receiving two doses of vaccine.     

Antibody response to vaccines for rhinotracheitis, caliciviral disease, panleukopenia, feline leukemia, and rabies in tigers (Panthera tigris) and lions (Panthera leo)

This article presents the results of a study of captive tigers (Panthera tigris) and lions (Panthera leo) vaccinated with a recombinant vaccine against feline leukemia virus; an inactivated adjuvanted vaccine against rabies virus; and a multivalent modified live vaccine against feline herpesvirus, calicivirus, and panleukopenia virus. The aim of the study was to assess the immune response and safety of the vaccines and to compare the effects of the administration of single (1 ml) and double (2 ml) doses. The animals were separated into two groups and received either single or double doses of vaccines, followed by blood collection for serologic response for 400 days. No serious adverse event was observed, with the exception of abortion in one lioness, potentially caused by the incorrect use of the feline panleukopenia virus modified live vaccine. There was no significant difference between single and double doses for all vaccines. The recombinant vaccine against feline leukemia virus did not induce any serologic response. The vaccines against rabies and feline herpesvirus induced a significant immune response in the tigers and lions. The vaccine against calicivirus did not induce a significant increase in antibody titers in either tigers or lions. The vaccine against feline panleukopenia virus induced a significant immune response in tigers but not in lions. This report demonstrates the value of antibody titer determination after vaccination of nondomestic felids.     

The influence of maternal immunity on the efficacy of a classical swine fever vaccine against classical swine fever virus,genogroup 2.2, infection

In Thailand, where vaccination is routinely employed, there has been an increased incidence of chronic classical swine fever (CSF) outbreaks during the past decade. The major causative virus has been identified to be the moderate virulence, classical swine fever virus (CSFV) of the genogroup 2.2. An investigation was made into the efficacy of a CSF vaccine against this genogroup 2.2 challenge. Five-week-old pigs, grouped by their level of passive antibody titer were immunized with lapinized Chinese-strain CSF vaccine and challenged with CSFV genogroup 2.2, 13 days after vaccination. The group containing passive titers of lower than 64 at the time of immunization, had significantly higher number of CSFV-specific IFN-gamma secreting cells and was completely protected against the challenge. Interestingly, both cellular and antibody responses were inhibited in the pigs with the higher passive titer. Furthermore, following challenge, CSFV could be isolated from 50% of the pigs in this group. It was demonstrated that the CSF vaccine could induce complete protection in pigs, provided that the maternal derived titer at the time of vaccination was lower than 64. The result implied that an increase in CSFV outbreaks might be due to the inappropriate timing of vaccination as well as the nature of the CSFV genogroup 2.2.     

Comparative investigations of a combined vaccine against parvovirus and erysipelas and corresponding monovaccines in different vaccination schedules. 1: Field trial]

In a field trial, the development of antibodies of a combined vaccine against the porcine parvovirus (PPV) as well as against swine erysipelas was compared with corresponding mono vaccines. Furthermore, these vaccines were used in different vaccination schedules. The tests were carried out on 109 gilts in three closed farms. In all gilts, a basic immunization repeated twice was carried out at the age of six months and at intervals of three weeks. The revaccination was carried out four months after the basic immunization with half of the animals, and six months after the basic immunization with the remaining gilts. Between the combined vaccine and the mono vaccine no significant differences in the development of antibodies against PPV could be found according to different vaccination schedules. The gilts having been vaccinated with the mono vaccine and boostered six months later showed significantly higher antibody titers against Erysipelothrix rhusiopathiae. Between the remaining vaccination groups no significant difference in the development of the antibodies against swine erysipelas could be found. On only one farm, a continuous decrease of antibody titers against PPV in case of altogether 238 non-vaccinated piglets until the sixth month of life could be observed. On the two other farms, an increase of antibody titers against PPV could be found at different points of time, which indicates an infection of the piglets. Between the individual vaccination groups no significant antibody titers against PPV could be measured in milk tests. With regard to the number of piglets born alive per litter, the number of piglets born dead per litter and the number of mummies, a significant difference could neither be found between the vaccination groups 1-4.     

Yeast-expressed classical swine fever virus glycoprotein E2 induces a protective immune response

Classical swine fever (CSF) is an economically important swine disease worldwide. The glycoprotein E2 of classical swine fever virus (CSFV) is a viral antigen that can induce a protective immune response against CSF. A recombinant E2 protein was constructed using the yeast Pichia pastoris expression system and evaluated for its vaccine efficacy. The yeast-expressed E2 (yE2) was shown to have N-linked glycosylation and to form homodimer molecules. Four 6-week-old specified-pathogen-free (SPF) piglets were intramuscularly immunized with yE2 twice at 3-week intervals. All yE2-vaccinated pigs could mount an anamnestic response after booster vaccination with neutralizing antibody titers ranging from 1:96 to 1:768. Neutralizing antibody titers at 10 weeks post booster vaccination ranged from 1:16 to 1:64. At this time, the pigs were subjected to challenge infection with a dose of 1 × 10⁵ TCID₅₀ (50% tissue culture infective dose) virulent CSFV strain. At 1 week post challenge infection, all of the yE2-immunized pigs were alive and without symptoms or signs of CSF. Neutralizing antibody titers at this time ranged from 1:4,800 to 1:12,800 and even to 1:51,200 one week later. In contrast, the control pigs continuously exhibited signs of CSF and had to be euthanized because of severe clinical symptoms at 6 days post challenge infection. All of the yE2-vaccinated pigs were E^rns antibody negative and had seroconverted against E^rns by post challenge day 11, suggesting that yE2 is a potential DIVA (differentiating infected from vaccinated animals) vaccine. The yeast-expressed E2 protein retains correct immunogenicity and is able to induce a protective immune response against CSFV infection.     

猪流感疫苗研究进展

全面综述了国内外猪流感（SI）疫苗的研究现状。从激发体液免疫、细胞免疫、交叉保护以及避免母源抗体干扰和区分野毒感染等方面分别阐述了常规疫苗、减毒疫苗、亚单位疫苗、DNA疫苗、病毒活载体疫苗的研究进展,以期找到最佳控制猪流感的疫苗及免疫方案,为进一步研究猪流感疫苗提供参考。