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1.
Foot and mouth disease (FMD) remains subclinical and self-limiting in small ruminants, but risk of spread of infection to susceptible cohorts is of great epidemiological significance; therefore, small ruminants must be included in vaccination campaigns in FMD endemic regions. Three groups of goats already immunized against peste des petits ruminants (PPR) were vaccinated with FMD and PPR vaccines alone or concurrently. The specific antibody response against three FMD virus strains and PPR virus were evaluated by competitive enzyme-linked immunosorbent assay (cELISA). Goats concurrently vaccinated with PPR + FMD vaccines had significantly (p < 0.05) higher antibody titers to two serotypes of FMD virus at 28, 45, and 60 days post-immunization compared to goats vaccinated with FMD vaccine alone, while goats vaccinated with PPR vaccines alone or PPR + FMD vaccines concurrently showed similar antibody kinetics against PPR virus up till 60 days post-vaccination. Overall, antibody kinetic curves for all three tested strains of FMD virus and PPR virus were similar in vaccinated groups during the course of experiment.  相似文献   

2.
Young calves were simultaneously vaccinated by subcutaneous route against foot-and-mouth disease (FMD) and against infectious bovine rhinotracheitis/adenovirus/parainfluenza-3 (IBR/Adeno/PI-3) by intranasal route. The serological response against the 3 FMD virus types of the FMD vaccine was clearly positive. There was no significant difference between results of simultaneous FMD and IBR/Adeno/PI-3 vaccination and FMD vaccination only.  相似文献   

3.
猪圆环病毒2型感染对猪瘟疫苗体液免疫应答的影响   总被引：3，自引：0，他引：3  
采用ELISA方法对单独接种猪瘟疫苗组(CSFV组,n=3)、PCV2感染且出现病毒血症后接种猪瘟疫苗组(PCV2/CSFV组,n=3)及PCV2感染同时接种猪瘟疫苗组(CSFV/PCV2组,n=3)不同时相血清中的猪瘟抗体进行检测;并对PCV2感染对照组(PCV2组)及PCV2/CSFV和CSFV/PCV2组血清中PCV2特异的抗体和核酸分别进行ELISA和PCR检测.结果表明,在接种后52 d CSFV组血清中抗体的阻断值显著高于CSFV/PCV2组(P<0.05);接种后42 d和52 d CSFV组平均抗体效价明显高于PCV2/CSFV和CSFV/PCV2组,其中在52 d CSFV组抗体阳性率这100%(3/3)而PCV2/CSFV和CSFV/PCV2在相应时相抗体阳性率仅为67%(2/3).结果提示PCV2感染可在一定程度上抑制猪瘟疫苗特异性的抗体反应.  相似文献   

4.
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。  相似文献   

5.
Protection against foot-and-mouth disease (FMD) and ability to transmit FMD virus to susceptible contact animals were studied in cattle vaccinated three times in annual field campaigns with the Dutch trivalent vaccine. Eighty vaccinated cattle and 16 susceptible controls were intranasally exposed to an aerosol containing a homologous FMD challenge virus (O1 BFS, A10 Holland or C1 Detmold) or a heterologous virus (A5 Modena or C1 Modena). The day after exposure, vaccinated cattle were stabled individually with an FMD-susceptible contact. All cattle challenged with an homologous virus strain at one year (20 head), at two years (10 head) and at three years (30 head) after the last vaccination were protected against the development of clinical signs of disease; one, zero and five cattle of these groups, respectively, transmitted virus to their contacts. In each group, approximately two out of three exposed cattle had virus-positive oropharyngeal fluid samples and seroconverted. The amount of virus recovered from probang samples increased with the time since the last vaccination. Mean antibody titres of cattle that had not been vaccinated for three consecutive years did not change significantly over the last two-year period. All 10 cattle challenged with the vaccine strain-related C1 Modena virus were protected against clinical disease, whereas three out of 10 challenged with the heterologous A5 Modena strain virus one year after the last vaccination contracted FMD and transmitted the virus. Five others (four in the C1 group and one in the A5 group) spread the virus to their contacts.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

6.
As a result of the continuing threat of Venezuelan equine encephalomyelitis (VEE), a study was made to determine if revaccination against VEE (TC-83 vaccine) was feasible and if revaccination could be incorporated into other routine vaccination practices. Of the horses given annual vaccination with bivalent western equine encephalomyelitis (WEE) and eastern equine encephalomyelitis (EEE) vaccine, 57% retained detectable serum-neutralizing (SN) antiboyd titers for VEE 18 months after the initial VEE vaccination was given. Of horses with no record of WEE-EEE vacinnation, 100% retained detectable VEE SN antibody titers over the same period. The VEE geometric mean titer was 25 times greater for horses not previously vaccinated against WEE-EEE than for horses given annual WEE-EEE vaccination at the time of VEE vaccination. In horses vaccinated against VEE 18 months previously, the geometric mean titer increased from 4 to 70 at 48 days after the intitial WEE-EEE vaccination. This increase indicated that similar antigenic factors for VEE are possibly present in bivalent WEE-EEE vaccine. In horses previously vaccinated against WEE-EEE and VEE, the best SN antibody response to VEE revaccination occurred when VEE vaccine was given simultaneously with the bivalent WEE-EEE vaccine. Of 150 serum samples tested by both the SN and the hemagglutination-inhibiton tests, agreement between positive reactions at greater than or equal to 1:10 was 70% for VEE, 81% for EEE, and 87% for WEE.  相似文献   

7.
Young calves were vaccinated with Belgian foot-and-mouth disease (FMD) vaccine and revaccinated with either the same vaccine or with a foreign FMD vaccine.There was a significant serological response to the primary vaccine strains after the first vaccination which was greater following revaccination. At one and two months after revaccination there was no significant difference between the responses to revaccination with vaccine identical to the primary vaccine or with the foreign FMD vaccine.It was concluded that revaccination of young calves is effective even with an FMD vaccine different from the primary vaccine.  相似文献   

8.
This study was conducted to determine if humoral antibody response of foot-and-mouth disease (FMD) vaccine improved in 8-week-old growing pigs born to well-vaccinated sows pre-treated with 60 mg of poly-γ-glutamic acid (γ-PGA) three days before vaccination. Antibody against FMD virus serotype O was measured 0, 2, 4 and 6 weeks post-vaccination, using a PrioCHECK FMDV type O ELISA kit. The results showed that positive antibody reactions against FMDV serotype O antigen among a component of the vaccine significantly increased in response to pre-injection with γ-PGA.  相似文献   

9.
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。  相似文献   

10.
Small ruminants play an important role in the epidemiology of Foot-and-Mouth Disease (FMD). Small ruminants are vaccinated with one-half or one-third of cattle dose of oil-based or aqueous vaccines respectively. The extinction antigen payload in vaccine for protection in small ruminants is poorly studied. FMD seronegative Nellore sheep (n=30) and Osmanabadi goats (n=30) were vaccinated with different payloads of O(1) Manisa vaccine (0.45-5 μg). Vaccinated and sero-negative unvaccinated sheep (n=6) and goats (n=6) were challenged intradermally into the coronary band with O(1) Manisa virus. The sheep and goats were monitored for signs of FMD and samples were collected for measuring viraemia and virus associated with nasal swabs and probang samples. Clotted blood was collected for serology. Vaccines containing antigen payload up to 0.94 μg protected sheep and goats against challenge. Sheep and goats vaccinated with 0.45 μg antigen payload were poorly protected against challenge. An antigen payload of 0.94 μg was sufficient to offer complete protection and also absence of carrier status. Sheep and goats with no vaccination or with poor sero conversion to vaccination showed sub-clinical infection and became carriers. The results of the study suggest that vaccination offers protection from clinical disease even at a low payload of 0.94 μg and hence one-half of cattle dose of the oil-based vaccine formulations is sufficient to induce protective immune response in sheep and goats. Since no live virus could be isolated after 5 days post challenge from the nasal swab or probang samples even though viral RNA was detected, the risk of these animals transmitting disease was probably very low.  相似文献   

11.
In this study, we investigated whether Cedivac-FMD, an emergency vaccine against foot-and-mouth disease (FMD), is suitable for use conjointly with a screening program intended to confirm freedom from disease in vaccinated herds based on evidence of virus replication in vaccinates. Different sets of sera were tested using the Ceditest FMDV-NS ELISA for the detection of antibodies against non-structural proteins (NSPs) of FMD virus. During a vaccine safety study, serum samples were collected from 10 calves, 10 lambs and 10 piglets following administration of a double dose and a repeat dose of high payload trivalent Cedivac-FMD vaccine. All serum samples collected both 2 weeks following the administration of a double dose as well as those collected 2 weeks after the single dose booster (given 2 weeks after the double dose) were negative in the Ceditest FMDV-NS ELISA. In a series of vaccine potency experiments, serum samples were collected from 70 vaccinated cattle prior to and following exposure to infectious, homologous FMD virus. When testing cattle sera collected 4 weeks after vaccination with a regular dose of monovalent >6 PD(50) vaccines, 1 of 70 animals tested positive in the NSP antibody ELISA. After infection with FMD virus, antibodies to NSP were detected in 59 of 70 vaccinated cattle and 27 of 28 non-vaccinated control animals within 7 days. Cedivac-FMD vaccines do not induce NSP antibodies in cattle, pigs or sheep following administration of a double dose or a repeat dose. FMD-exposed animals can be detected in a vaccinated group within 7-14 days. Because Cedivac-FMD does not induce NSP antibodies, the principle of 'marker vaccine' applies.  相似文献   

12.
Classical swine fever (CSF) causes major losses in pig farming, with various degrees of disease severity. Efficient live attenuated vaccines against classical swine fever virus (CSFV) are used routinely in endemic countries. However, despite intensive vaccination programs in these areas for more than 20 years, CSF has not been eradicated. Molecular epidemiology studies in these regions suggests that the virus circulating in the field has evolved under the positive selection pressure exerted by the immune response to the vaccine, leading to new attenuated viral variants. Recent work by our group demonstrated that a high proportion of persistently infected piglets can be generated by early postnatal infection with low and moderately virulent CSFV strains. Here, we studied the immune response to a hog cholera lapinised virus vaccine (HCLV), C-strain, in six-week-old persistently infected pigs following post-natal infection. CSFV-negative pigs were vaccinated as controls. The humoral and interferon gamma responses as well as the CSFV RNA loads were monitored for 21 days post-vaccination. No vaccine viral RNA was detected in the serum samples and tonsils from CSFV postnatally persistently infected pigs for 21 days post-vaccination. Furthermore, no E2-specific antibody response or neutralising antibody titres were shown in CSFV persistently infected vaccinated animals. Likewise, no of IFN-gamma producing cell response against CSFV or PHA was observed. To our knowledge, this is the first report demonstrating the absence of a response to vaccination in CSFV persistently infected pigs.  相似文献   

13.
CP7_E2alf is a promising marker vaccine candidate against classical swine fever (CSF). To better understand the mechanisms of protection, cytokine and isotype-specific antibody profiles were investigated in CP7_E2alf vaccinated pigs before and after challenge with the highly virulent CSFV strain “Koslov” at 14 days or 6 months post-vaccination. The interference of vaccination with CSFV pathogeny-related cytokine responses, previously described following a moderately virulent challenge, was confirmed. However, the levels of additional cytokines, TNF-α and IL-6, were significantly attenuated by vaccination following highly virulent challenge. This vaccine interference with cytokine response was not dependent on the immunization route or the consequence of competition between vaccine and challenge strain. Interestingly, IFN-γ enhancement and persistent high IgG2 levels suggested an important role of cell-mediated immunity in long-term protection against CSFV induced by CP7_E2alf vaccination. IgA production also revealed a stimulation of mucosal immunity, especially after oral administration of the vaccine.  相似文献   

14.
We studied the efficacy of multiple vaccinations of wild boar against classical swine fever (CSF) using a C-strain vaccine. The study consisted of two experiments. In the first experiment, 7 to 8 months old animals were vaccinated either three or four times at an interval of 7 days or twice at an interval of 14 or 28 days. In the second experiment, the efficacy of oral immunisation in young boars (3 months old) was examined after fivefold vaccination at intervals of 14 or 28 days. Independently of the immunisation scheme all wild boar developed neutralising antibodies. An evaluation of the antibody titres 28 days after the initial vaccine application showed that single vaccination and triple immunisation at an interval of 7 days induced the highest antibody titres (X > or = 1/80). In multiple vaccinated young boars (vaccinated at intervals of 14 or 28 days) the third vaccination led to a slight reduction or to an only moderate increase of the antibody titre. In a challenge study after the fifth vaccination all wild boar were protected (no viraemia, no virus excretion, no post-mortem virus detection in organs). This was confirmed by the fact that sentinel animals were not affected. Although other immunisation schemes also were effective, booster vaccination at an interval of 28 days is recommended as basic procedure for eradication of CSF in wild boar. Triple vaccination might also be used at the beginning of the control measures.  相似文献   

15.
The efficacy of two marker vaccines against classical swine fever (CSF) was tested in a large scale laboratory trial in several National Swine Fever Laboratories (NSFL) of the EU member states. The vaccines were: BAYOVAC CSF Marker (Vaccine A) from Bayer, Leverkusen, Germany and PORCILIS PESTI (Vaccine B) from Intervet, Boxmeer, The Netherlands. At the NSFL of Belgium, The Netherlands and Germany experiments were carried out to examine the ability of the vaccines to prevent transplacental transmission of CSF virus. In Belgium and The Netherlands pregnant sows were vaccinated once and challenged with virulent CSF virus 14 days later, which was around day 60 of gestation. At the NSFL in Germany sows were vaccinated twice, on days 25 and 46 of pregnancy and were challenged fourteen days after booster vaccination (day 60 of gestation). Apart from minor inflammatory reactions in some sows, no reactions post vaccination were noticed in either vaccine group. Sows vaccinated with Vaccine A were better protected against clinical CSF than sows vaccinated with Vaccine B. The antibody response after vaccination with Vaccine A was more pronounced than after vaccination with Vaccine B. After single vaccination six out of eight sows vaccinated with Vaccine A and all eight sows vaccinated with Vaccine B had viraemic piglets. After double vaccination one out of four litters from sows vaccinated with Vaccine A and four out of five litters from sows vaccinated with Vaccine B were found to be viraemic. However, both vaccines reduced the transmission probability significantly (Vaccine A: P=0.004, Vaccine B: P=0.024) after booster vaccination. However, Vaccine A appeared in this regard more potent as the estimated probability of fetal infections was lower. Nevertheless the risk of virus spreading after vaccination via transplacental transmission is still present and has to be addressed from an epidemiological point of view.  相似文献   

16.
将猪瘟弱毒脾淋疫苗、猪O型口蹄疫灭活疫苗(Ⅱ)和高致病性猪蓝耳病灭活疫苗采用两两组合的方式同时分部位免疫35日龄左右的健康仔猪,观察并记录其免疫反应。在疫苗免疫后0、4、14、21d和28d无菌取猪血清,用ELISA检测免疫后三种疫苗抗体水平的动态变化。试验结果表明:猪瘟和猪口蹄疫疫苗同时免疫,效果较好;猪口蹄疫和高致病性猪蓝耳病疫苗同时免疫,效果较差;猪瘟疫苗和高致病性猪蓝耳病疫苗同时免疫,效果不明显,还需进一步验证。  相似文献   

17.
为探索猪圆环病毒2型(PCV2)感染对猪瘟(CSF)弱毒疫苗接种猪免疫应答的影响,将20头28 d断奶仔猪随机分为V-I、I-V、V和C4组,5头·组-1.V-I组在接种CSF弱毒疫苗后2d感染PCV2;I-V组在感染PCV2 后2d接种CSF弱毒疫苗;V组只接种CSF弱毒疫苗;C组为空白对照组.共免疫2次,间隔21 d.免疫后定期检测血清CSFV特异性抗体水平、外周血淋巴细胞(PBLC)增殖活性和PBLC中IFN-γ、IL-2、IL-4和IL-10 mRNA的表达水平.结果显示:在CSF弱毒疫苗免疫前或免疫后感染PCV2,均会导致CSFV抗体水平低下,血清抗体阳转率下降,PBLC增殖活性降低.初次免疫后,V-I与I-V组的PBLC内IFN-γ、IL-2、IL-4和IL-10 mRNA的表达量严重不足,其中V-I组的表达量最低.加强免疫后V-I与I-V组的PBLC内IFN-γ与IL-10的表达失衡,IL-2和IL-4的表达缺乏,其中I-V组的细胞因子表达失衡和缺乏更严重.上述研究表明,CSF弱毒疫苗免疫前或免疫后感染PCV2均会影响机体的体液和细胞免疫应答水平,导致PBLC内细胞因子的表达严重抑制和紊乱.  相似文献   

18.
L W Jen  B R Cho 《Avian diseases》1980,24(4):896-907
Studies were made to determine whether infectious bursal disease virus (IBDV) infection would affect the response of chickens to turkey herpesvirus (HVT) vaccination in the development and level of HVT viremia and virus-neutralizing (VN) antibodies to HVT. The HVT viremia in the vaccinated chickens was not affected by IBDV, whether IBDV was inoculated simultaneously with HVT vaccination at one day of age or whether it was inoculated 3 weeks postvaccination with HVT. However, VN antibody response to HVT was significantly suppressed (P less than 0.001) when vaccinated chickens were exposed to IBDV either at the time of vaccination or at 3 weeks postvaccination. Such immunosuppression by IBDV of VN antibody response to HVT vaccination may result in a reduced antiviral immunity against Marek's disease virus.  相似文献   

19.
The period during which pigs are protected after vaccination is important for the successful usage of a marker vaccine against classical swine fever virus (CSFV) in an eradication programme. In four animal experiments with different vaccination-challenge intervals we determined the duration of protection of an E2 subunit marker vaccine in pigs after a single vaccination. Unvaccinated pigs were included in each group to detect transmission of the challenge virus.Three groups of six pigs were vaccinated once and subsequently inoculated with the virulent CSFV strain Brescia after a vaccination-challenge interval of 3, 51/2, 6 or 13 months. All vaccinated pigs, 16 out of 18, with neutralising antibodies against CSFV at the moment of challenge, 3, 51/2, 6 or 13 months later, survived, whereas unvaccinated control pigs died from acute CSF or were killed being moribund. A proportion of the vaccinated pigs did however develop fever or cytopenia after challenge and two vaccinated pigs were viremic after challenge. Virus transmission of vaccinated and challenged pigs to unvaccinated sentinel pigs did not occur in groups of pigs which were challenged 3 or 6 months after a single vaccination. Two out of eight vaccinated pigs that were found negative for CSFV neutralising antibody at 13 months after vaccination died after subsequent challenge.The findings in this study demonstrate that pigs can be protected against a lethal challenge of CSFV for up to 13 months after a single vaccination with an E2 subunit marker vaccine.  相似文献   

20.
Foot-and-mouth disease (FMD) is an economically important disease of cloven-hoofed animals that is primarily controlled by vaccination of susceptible animals and movement restrictions for animals and animal-derived products in South Africa. Vaccination using aluminium hydroxide gel-saponin (AS) adjuvanted vaccines containing the South African Territories (SAT) serotypes has been shown to be effective both in ensuring that disease does not spread from the endemic to the free zone and in controlling outbreaks in the free zone. Various vaccine formulations containing antigens derived from the SAT serotypes were tested in cattle that were challenged 1 year later. Both the AS and ISA 206B vaccines adjuvanted with saponin protected cattle against virulent virus challenge. The oil-based ISA 206B-adjuvanted vaccine with and without stimulators was evaluated in a field trial and both elicited antibody responses that lasted for 1 year. Furthermore, the ISA 206 adjuvanted FMD vaccine protected groups of cattle against homologous virus challenge at very low payloads, while pigs vaccinated with an emergency ISA 206B-based FMD vaccine containing the SAT 1 vaccine strains were protected against the heterologous SAT 1 outbreak strain.  相似文献   

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