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1.
Newcastle disease virus strain I2--a prospective thermostable vaccine for use in developing countries. 总被引：6，自引：0，他引：6
Forty-five avirulent Australian strains of Newcastle disease virus had been examined for antigenicity in chickens and 18 of these were tested for thermostability. Strain I2, chosen for a combination of antigenicity and thermostability, was artificially selected for enhanced thermostability. Master seed material was then prepared in minimal disease eggs, and vaccine by a further two passages in conventional eggs. Strain I2 virus at seed and vaccine level induced adequate levels of antibody in chickens vaccinated by eye drop and usually in their contacts. The serological response to oral vaccination was less certain. Antibody titres indicative of substantial protection against virulent challenge were maintained in a simulated village flock for 38 weeks by vaccination of the foundation flock on two occasions, with subsequent vaccination confined to clutches of chicks as they were produced. Strain I2 virus survived for at least 12 weeks when stored at 22 degrees C in 1% gelatin. Strain I2 is suitable for local production of thermostable vaccine in regional laboratories in developing countries. 相似文献
2.
SUMMARY: Australian lentogenic Newcastle disease viruses were evaluated as uninactivated vaccines in Australian chickens, the response being evaluated by the production of haemagglutination-inhibition (HI) antibodies. Two viruses, V4 and PM9, induced high levels of antibody and were readily transmissible between chickens by contact exposure. Three other viruses were poorly immunogenic and poorly transmissible. Chickens vaccinated intramuscularly with the V4 strain produced higher HI antibody titres than chickens vaccinated by the orotracheal, intranasal and intraocular routes. HI antibody titres in chickens vaccinated with the V4 strain reached peak levels 3 to 5 weeks after vaccination and waned considerably during the next 2 to 4 weeks. However, low levels of HI antibody persisted for at least 36 weeks after vaccination. Intramuscular vaccination with the V4 strain of one-day-old chicks lacking maternal antibody to Newcastle disease virus resulted in 42–70% mortality and the survivors developed very high titres of HI antibody. Similar chickens inoculated orotracheally showed signs of depression and developed high titres of HI antibody, but there were no mortalities. Chickens 1-, 2-, 3- and 4-weeks-old and lacking maternally derived HI antibody to Newcastle disease virus suffered no adverse reaction to intramuscular or orotracheal vaccination. The antibody response of the 1-week-old chickens was considerably poorer than that of the older chickens. Following orotracheal vaccination with the V4 strain, chickens with low levels of maternally derived antibody responded with low levels of HI antibody. On the other hand, in the progeny of hens hyperimmunised with the V4 strain the production of active antibody following orotracheal vaccination was delayed until the level of passive antibody had declined considerably. There was no response to intramuscular vaccination in congenitally hyperimmune chickens. The minimum HI antibody inducing dose of V4 vaccine, when measured 3 weeks after vaccination of 6-weeks-old chickens, was 105.6 50% egg infectious doses. 相似文献
3.
The V4 strain of Newcastle disease virus was introduced into a small open range flock of bantam chickens, by dosing half the birds directly into the crop. As indicated by rises in titres of haemagglutination inhibition antibody, the virus spread to the uninoculated birds and persisted in the flock for two years, infecting chickens that were introduced by natural brooding and rearing. All new clutches of chicks seroconverted by 80 days of age, and the titres of adult birds showed a concurrent rise, suggesting that the chicks were amplifying the virus. The modes of spread and of persistence of the virus were not determined; although cloacal swabs were taken regularly, only one yielded virus. Antibody titres of the inoculated birds remained above the presumptive protective level of 3 (log2) for over a year, whereas the titres of birds infected by contact were generally less than 3. 相似文献
4.
本试验进行了三批鸡的免疫研究。第一批试验检测不同类型新城疫疫苗在不同母源抗体水平（高和低）的鸡体上的免疫效果。结果显示,在高母源抗体时免疫,Ｖ４组和油乳剂灭活苗级抗体水平表现较低,而在低母源抗体时免疫,几种疫苗的抗体水平上升得很快,特别Ｌａｓｏｔａ－克隆３０组最明显,而油乳剂灭活苗组的抗体水平保持最长。根据此结果而制定了不同的免疫程序,进行了第二、第三批免疫试验,并分别在４５天龄及７０天龄时进行强 相似文献
5.
The transfer of parental immunity to infectious laryngotracheitis was appraised by measuring serum antibody levels in 150 chicks from the day of hatch up to five weeks. The breeder flock which had received primary vaccination at eight weeks and a booster at 20 weeks transferred high antibody levels which fell markedly within two weeks and remained constant thereafter. Chicks whose parents were vaccinated at 20 weeks only, had low antibody levels throughout. These low levels, in either group of chicks, appeared to offer marginal protection only and were unlikely to inhibit the response to primary vaccination. 相似文献
6.
《The Journal of Applied Poultry Research》2007,16(2):187-191
Reoviruses are an important cause of suboptimum performance in commercial broilers worldwide. Integrators use the enzyme-linked immunosorbent assay against the S1133 antigen for monitoring serum of breeders for indicating pullet vaccine success. However, without correlating serology to reovirus challenge, it is difficult to determine whether titers reflect protective immunity. We developed a broiler challenge test against 2 common reovirus isolates (2408 and S1133) to evaluate the efficacy of reovirus pullet vaccine programs. Two reovirus serologic and challenge studies were undertaken using chicks from broiler integrators from the southeastern United States. Breeder flocks, from which the chicks were obtained, received at least 1 live and 2 inactivated reovirus vaccines during their pullet phase. One-day-old progeny were collected from 6 breeder flocks. At 1 d of age, 20 chicks from each broiler flock were bled, and serum was analyzed for antibodies. At 3 to 4 d of age, 20 progeny per flock were challenged with the 2408 reovirus by intratracheal route. At 10 to 14 d of age, another 20 birds per flock were challenged with the S1133 reovirus by footpad. Twenty birds per flock were used as nonchallenged controls. At 3 wk of age, all birds were killed and weighed. Percentage of protection was calculated for each flock based on the absence of gross lesions. Flocks with at least 50% protection were considered well protected. Most flocks were well protected against both viruses. The percentage of protection correlated with day-old enzyme-linked immunosorbent assay titers. Chicks from younger hens had higher titers and the best protection against challenge. Producers, whose hen flocks were monitored herein, were doing a good job of immunizing pullets against reovirus. They are now using reovirus progeny challenge studies along with breeder antibody titers to determine vaccination success of their pullets. 相似文献
7.
SUMMARY An experimental vaccine containing the avirulent Australian V4 strain of Newcastle disease virus was used to vaccinate 3- or 6-week-old chickens by aerosol and drinking water application. The chickens lacked maternally derived antibody to Newcastle disease virus. When the vaccine virus was diluted in tap water more than 90% of the infectivity was destroyed immediately. The addition of 0.25% skim milk prevented this loss and there was no loss in distilled water. Rates of inactivation at 37°C were similar in tap water and distilled water and were unaffected by the addition of skim milk. Both methods of vaccination resulted in the production of haemagglutination-inhibition antibodies which persisted for at least 8 to 12 weeks. The antibody response to aerosol vaccination was significantly better than that following drinking water vaccination. No clinical disease was induced by exposure to vaccine virus. Serum neutralisation antibodies paralleled those detected by haemagglutination-inhibition in chicks vaccinated once by drinking water. After revaccination through the drinking water, haemagglutination-inhibition antibodies were boosted temporarily while neutralising antibodies were maintained at an enhanced level. From chickens vaccinated by aerosol, Newcastle disease virus was recovered for 10 days from lungs and for 7 days from tracheas and caecal tonsils. Peak viraemia was detected 2 and 3 days after vaccination while both neutralising and haemagglutination-inhibition antibodies became detectable 5 days after vaccination. 相似文献
8.
S S Saini S S Sodhi N K Maiti S N Sharma 《Comparative immunology, microbiology and infectious diseases》1990,13(1):1-6
The humoral immune response and immunity conferred in chicks were compared following separate and combined oral vaccination with F strain of Newcastle disease virus (NDV) and HP1 strain of fowl pox virus. The haemagglutination inhibition (HI) antibody titre against NDV and passive haemagglutination (PHA) antibody titre against fowl pox virus were comparable in two respective groups. The serum IgG concentration increased significantly after the second vaccination in all the groups. The NDV vaccine induced significantly higher IgG production as compared to fowl pox virus vaccine. There was no significant difference in serum IgG concentration produced by combined vaccine and separate F strain vaccine. The protection afforded by combined and separate vaccinations did not vary significantly against challenge with virulent strains of NDV and fowl pox virus at different stages. 相似文献
9.
Antibody response was rapid and high in broiler breeder chickens receiving 1 or 2 vaccinations with oil-emulsion vaccine against Newcastle disease at 23 or at 23 and 26 weeks old. The antibody titers remained high during the 41-week experimental period. At 64 weeks old, about 41 weeks after vaccination, the geometric mean hemagglutination-inhibition antibody titer was 67 from the single vaccination, and 103 from the double vaccination. The immune response to live-virus vaccine given at 2, 9, 20, 30, 42, or 54 weeks of age via the drinking water was high, but uniformity was lacking in the antibody response in the breeders and maternal antibody response in the progeny. Maternal antibody levels in one-day-old chicks were related to the titers of antibody in the dams. Maternal antibody titers of chicks originated from breeder flocks that were vaccinated with the oil-emulsion vaccine remained high for all hatches. 相似文献
10.
Broiler chicks from a parent flock previously vaccinated with a commercial tenosynovitis (viral arthritis) vaccine were challenged when one day old with a virulent form of the vaccinal reovirus strain. A group from unvaccinated parents was similarly challenged. At three weeks after infection it was found that, while maternal antibody reduced the incidence of lesions of tenosynovitis by about 50 per cent and also the amount of virus in the gut when compared with the group without maternal antibody, the rates of recovery of virus from the hock joints were very similar. The possible epidemiological importance of persistent virus in the joints of clinically protected chicks is discussed. 相似文献
11.
用新城疫病毒La Sota株作为复合物疫苗抗原,与新城疫特异性中和抗体混匀配制成4种不同比例的复合物疫苗,用1日龄普通雏鸡进行免疫效果对比试验。试验1~4组分别为免疫复合物疫苗1~4,试验5组免疫常规新城疫活苗,试验6组为空白对照组。免疫后3周采血测定HI抗体效价,同时用新城疫强毒北京株F48E9攻击。试验结果显示,试验1~6组HI抗体效价分别为3.2log2、3.1log2、3.3log2、3.2log2、3.1log2、2.9log2;攻毒后,试验1~6组鸡的死亡率分别为15%、20%、0%、35%、30%、50%。因此,新城疫病毒La Sota株与新城疫特异性抗体制备成复合物疫苗,能保持疫苗中抗原的免疫原性,并可减轻疫苗的毒副作用,提高疫苗的安全性,其免疫效果比常规活苗好。 相似文献
12.
Chickens vaccinated with infectious bursal disease virus (IBDV) early in life and revaccinated with an inactivated, oil-adjuvant IBDV vaccine at 18 weeks of age produced and maintained high levels of virus-neutralizing (VN) antibody through 10 months of lay. VN-antibody titers of chicks hatched from eggs laid during the same period closely matched the average VN-antibody titers of the dams. A sequential study of the decline rates of IBDV maternal antibody (MAB) in unvaccinated and IBDV-vaccinated chicks showed that the vaccine virus did not accelerate the antibody depletion rate in vaccinated chicks. Chicks carrying high IBDV MAB showed no active immune response to vaccination with commercial IBDV vaccines. They were also refractory to a pathogenic field isolate of IBDV (FV). However, chicks with low levels of MAB responded to both vaccine virus and the FV, although their response to vaccine virus was milder and delayed. 相似文献
13.
IG BELL PJ NICHOLLS C. NORMAN AINI IDERIS† GM CROSS† 《Australian veterinary journal》1991,68(3):97-101
Meat chickens housed on a commercial broiler farm in Australia were vaccinated once at 10 to 11 days-of-age by aerosol with live V4 Newcastle disease virus (NDV) vaccine. Groups of vaccinated and unvaccinated birds were flown to Malaysia, where they were challenged with a virulent strain of NDV. Survival rates in vaccinated chickens challenged 7, 14, 21 or 31 d after vaccination were 0.47, 0.77, 0.97 and 0.92, respectively. All unvaccinated chickens died due to Newcastle disease (ND) following challenge. Chickens in Australia and Malaysia were bled and the serums tested for haemagglutination-inhibiting (HI) antibody to NDV. Many vaccinated birds with no detectable antibody, and all birds with a log2 titre of 2 or greater, survived challenge. The results showed that this V4 vaccine induced protective immunity in a significant proportion of chickens within 7 d of mass aerosol vaccination. This early immunity occurred in the absence of detectable circulating HI antibody. Non-HI antibody mediated immunity continued to provide protection up to 31 d after vaccination. Almost all vaccinated birds were protected within 3 w of vaccination. It is concluded that the V4 vaccine is efficacious and could be useful during an outbreak of virulent ND in Australia. 相似文献
14.
鸡新城疫－传染性支气管炎－传染性法氏囊病三联灭活疫苗对不同日龄雏鸡的免疫效力研究 总被引：1，自引：1，他引：0
为评估鸡新城疫（ND）-传染性支气管炎（IB）-传染性法氏囊病（IBD）三联灭活疫苗对不同日龄和不同水平母源抗体雏鸡的免疫效力和持续期,本试验用该疫苗免疫7、14、21日龄SPF雏鸡和有母源抗体的普通雏鸡,免疫后采血测定ND血凝抑制抗体（HI Ab）、IB血凝抑制抗体（HI Ab）及IBD中和抗体（NA）,并用传染性法氏囊病病毒（IBDV）强毒攻击。结果显示,7日龄SPF雏鸡免疫后21 d ND HI抗体、IB HI抗体及IBD中和抗体效价分别为7.9log2、6.9log2和14.1log2,SPF鸡日龄越大,抗体水平越高;28日龄SPF鸡免疫后3个月,0.3 mL免疫剂量组试验鸡ND HI、IB HI及IBD中和抗体效价分别达6.5log2、6.1log2和13.6log2,IBDV攻毒保护率均为100%（10/10）;不同日龄普通雏鸡免疫效果与SPF鸡试验一致,抗体水平随鸡日龄增大而升高,IBD攻毒保护率也都达到100%（10/10）。试验结果证实,鸡新城疫-传染性支气管炎-传染性法氏囊病三联灭活疫苗可使7、14及21日龄SPF雏鸡和普通雏鸡产生良好的免疫力,对雏鸡的免疫期至少为3个月。 相似文献
15.
W Solano J J Giambrone J C Williams L H Lauerman V S Panangala C Garces 《Avian diseases》1986,30(4):648-652
Maternal antibody titers in white leghorn chicks against infectious bursal disease virus (IBDV) were measured by a computer-assisted, single-serum-dilution, indirect kinetic-based enzyme-linked immunosorbent assay (KELISA) and by a virus-neutralization (VN) test in order to predict the timing of initial vaccination. Day-old white leghorns were from unvaccinated pullets or from pullets vaccinated either four times or twice with IBDV commercial vaccines. The chicks were immunized once via the drinking water with a commercial "intermediate" live IBDV vaccine at 1, 15, or 28 days of age. Effective initial immunization was confirmed by an increase in antibody to IBDV (serologic conversion) that occurred when maternal antibody decreased to 8 and 9 on a log2 scale. This concentration of antibody was detected between 24 and 28 days of age. The computer-assisted IBDV-KELISA increased the sample processing speed for detecting IBDV antibody, and it was as sensitive as the VN test for predicting the timing of initial IBDV vaccination. 相似文献
16.
Avian metapneumovirus (aMPV) is an important cause of disease in chickens and turkeys. As infection can occur early in life and spread of the virus throughout a flock is rapid, an early onset of immunity post-vaccination would be advantageous. We have studied the serological immune response and the onset of protective immunity of an aMPV vaccine delivered to chickens via the in ovo route compared to oculonasal delivery at day old. A 1000-fold lower dose delivered in ovo to chicken specific pathogen free (SPF) embryos, than vaccination at day old, provided a significantly higher antibody response. In the presence of maternally derived antibody (MDA), there was no significant difference in antibody response between the vaccination routes. However, the onset of immunity (OOI) for the vaccine delivered to MDA positive chicken embryos was 5 days post-hatch in comparison to 8 days post-hatch for the same dose of vaccine given at day old indicating that chicks would be protected against disease earlier in the field if vaccinated by the in ovo route. In further experiments the OOI for a turkey vaccine delivered to MDA positive turkey embryos was shown to be 8 days post-hatch. 相似文献
17.
Antibody responses to avian encephalomyelitis virus vaccines when administered by different routes 总被引：1，自引：0，他引：1
Antibody responses to a commercial avian encephalomyelitis virus (AEV) vaccine administered by different routes were measured by an enzyme-linked immunosorbent assay (ELISA). Responses to single doses of vaccine administered by the ocular route to 10% of a flock were comparable with those obtained when all birds received a single dose in the drinking water. However, ocular vaccination of 5% of the flock resulted in significantly lower responses than those obtained when 10% were vaccinated. Maternal antibody was shown by the ELISA to persist in chickens from vaccinated flocks for up to 21 days after hatching. Day-old chickens with serum absorbances of < 0.3 at 492 nm, as determined by the ELISA, were shown to be susceptible to intracerebral challenge with the neurotropic Van Roekel strain of AEV. 相似文献
18.
Two experiments were conducted to determine the effect of breeder vaccination program and maternal antibody on the efficacy of Newcastle disease immunization of 1-day-old chicks. Experimental protocol was the same for both. In the first experiment, broilers were from breeders that were 32 weeks old, and in the second experiment, broilers were from breeders 50 weeks old. Breeders received three live Newcastle disease virus (NDV) vaccines and either a killed vaccine at 18 weeks or continual live boosting at 60-to-70-day intervals through lay. Broilers were vaccinated at 1 day of age with a commercial coarse-spray machine; they were bled, sera were examined for antibody against NDV, and broilers were challenged with virulent NDV at 2, 4, and 6 weeks of age. In the first experiment, maternal antibody was higher in chicks from the younger breeders given the inactivated vaccine, and in the second experiment maternal antibody was higher in chicks from older breeders given continual live vaccines. Higher antibody in 1-day-old broilers resulted in fewer vaccine-induced reactions, less vaccine virus shed, and decreased duration of vaccine-induced immunity from coarse-spray vaccination. 相似文献
19.
Embryo vaccination with infectious bursal disease virus alone or in combination with Marek's disease vaccine 总被引：1，自引：0，他引：1
J M Sharma 《Avian diseases》1985,29(4):1155-1169
Studies with specific-pathogen-free chickens revealed that chicks hatching from eggs inoculated at the 18th day of embryonation with infectious bursal disease (IBD) vaccine viruses of low virulence (isolates TC-IBDV and BVM-IBDV) developed antibody against IBD virus (IBDV) and resisted challenge with virulent IBDV at 3 weeks of age or older. Embryo vaccination did not adversely affect hatchability of chicks or survival of hatched chicks. Chicks embryonally vaccinated with TC-IBDV had transient histologic lesions in the bursa of Fabricius at hatch. Similar but milder lesions were also noted in chickens that received TC-IBDV at hatch. The level of protection following embryo vaccination with TC-IBDV and BVM-IBDV was similar to that following vaccination with the same vaccines at hatch. Vaccine viruses of moderate virulence (isolates BV-IBDV and 2512-IBDV) were not suitable as vaccines in embryos lacking maternal antibody to IBDV, because the vaccinated chicks developed acute IBD after hatch. Isolate 2512-IBDV was not pathogenic for embryos bearing maternal antibody to IBDV. Maternal antibody against IBDV interfered with efficacy of embryo vaccination with BVM-IBDV but not with 2512-IBDV. Embryo vaccination with a mixture of vaccines against IBD and Marek's disease resulted in protection of hatched chicks against challenge with virulent IBDV and Marek's disease virus. 相似文献
20.
Saravanabava K Nachimuthu K Padmanaban VD 《Comparative immunology, microbiology and infectious diseases》2005,28(4):269-276
The effect of tuftsin of embryo and post-hatch vaccination with NDV-F was studied. The embryo vaccination with NDV-F resulted in more number of dead-in-shell embryos. To overcome this problem, the vaccine was treated separately with ethyl methane sulfate (EMS) and 5-fluorouracil (5-FU) and administered. Treating the vaccine with 5-FU resulted in better hatchability as compared to EMS treatment. In embryo, NDV antibody titres increased upto 2 weeks of age and declined thereafter, whereas in post-hatch vaccination, the antibody titre increased from second to fourth week of age and declined thereafter. The seroconversion was better when the vaccine was given along with tuftsin either to embryos or chicks (post-hatch vaccination) as compared to those vaccinated without tuftsin. Moreover, the percentage of hatchability was more in tuftsin administered groups. It was found that embryo vaccination can ensure definite protection during the early life of the chicks despite the presence of maternal antibodies. In cases where breeder vaccinations do not result in concomitant transfer of antibody to progeny chicks, embryo vaccination would give only neonatal resistance. During the later stages, embryo vaccination did not confer any advantage over post-hatch vaccination. 相似文献