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2.
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
3.
Development of a virosome vaccine for Newcastle disease virus 总被引：7，自引：0，他引：7
In an effort to protect chickens against Newcastle disease (ND), a nonreplicating virosome vaccine was produced by solubilization of Newcastle disease virus (NDV) with Triton X-100 followed by detergent removal with SM2 Bio-Beads. Biochemical analysis indicated that the NDV virosomes had similar characteristics as the parent virus and contained both the fusion and hemagglutinin-neuraminidase proteins. To target the respiratory tract, specific-pathogen-free chickens were immunized intranasally and intratracheally with the NDV virosome vaccine. This vaccine was compared with a standard NDV (LaSota) live-virus vaccine for commercial poultry. Seroconversion (> or = four fold increase in hemagglutination inhibition [HI] antibody titers) was achieved in all birds vaccinated with the virosome vaccine. Upon lethal challenge with a velogenic NDV strain (Texas GB), all birds receiving either vaccination method were protected against death. Antibody levels against NDV, as determined by enzyme-linked immunosorbent assay and HI titer, were comparable with either vaccine and increased after virus challenge. These results demonstrate the potential of virosomes as an effective tool for ND vaccination. 相似文献
4.
Newcastle disease (ND) is one of the most important diseases of poultry, and may cause devastating losses in the poultry industry worldwide. Its causative agent is Newcastle disease virus (NDV), also known as avian paramyxovirus type 1. Many countries maintain a stringent vaccination policy against ND, but there are indications that ND outbreaks can still occur despite intensive vaccination. It has been argued that this may be due to antigenic divergence between the vaccine strains and circulating field strains. Here we present the complete genome sequence of a highly virulent genotype VII virus (NL/93) obtained from vaccinated poultry during an outbreak of ND in the Netherlands in 1992-1993. Using this strain, we investigated whether the identified genetic evolution of NDV is accompanied by antigenic evolution. In this study we show that a live vaccine that is antigenically adapted to match the genotype VII NL/93 outbreak strain does not provide increased protection compared to a classic genotype II live vaccine. When challenged with the NL/93 strain, chickens vaccinated with a classic vaccine were completely protected against clinical disease and mortality and virus shedding was significantly reduced, even with a supposedly suboptimal vaccine dose. These results suggest that it is not antigenic variation but rather poor flock immunity due to inadequate vaccination practices that may be responsible for outbreaks and spreading of virulent NDV field strains. 相似文献
5.
The novel vaccination technique for feral pigeons was developed in the present study. Multi-age feral pigeons were vaccinated
orally with Newcastle disease (ND) strain I-2 vaccine coated on oiled rice. The results showed that 14 days after vaccination
40% of pigeons seroconverted with HI GMT of ≥3 log2 whereas 28 days after vaccination the seroconversion rate of these birds reached 100%. Moreover, all vaccinated pigeons survived
the challenge of virulent Newcastle disease virus (NDV). The findings from the present study indicated that the use of ND (strain I-2) vaccine in feral pigeons is feasible
and resulted into the production of protective antibody response. Thus ND I-2 vaccine may prevent the spread of NDV to other
birds particularly chickens. Furthermore the use of oral vaccine in feral multi-age pigeons overcomes the difficulty of catching
these birds for individual vaccination. 相似文献
6.
Antibody responses in indigenous village and commercial chickens vaccinated with 12 thermostable Newcastle disease (ND) vaccine and protection levels against challenge with a virulent field isolate were determined. The antibody response of village chickens vaccinated by eye drop revealed that 30, 60 and 90 days after primary vaccination, the mean log2 HI titres were 6.1, 5.4 and 3.6, respectively, whereas for commercial chickens, the antibody response after 14, 30 and 90 days were 8.2, 5.1 and 4.2, respectively. Village chickens vaccinated orally via drinking water had mean log2 HI titres of 3.4 after 30 days. After booster vaccination, the mean HI titre was 5.4 and 3.3 after 30 and 60 days post-secondary vaccination (i.e. 60 and 90 days after primary vaccination). Antibody response of mean log2 HI titres of 2.6 was recorded 30 days after primary vaccination orally through food; 30 and 60 days after secondary vaccination (i.e. 60 and 90 days after primary vaccination), mean log2 HI titres were 5.3 and 3.2, respectively. All commercial and village chickens vaccinated by eye drop survived the challenge trial whereas village chickens vaccinated through drinking water and food had protection levels of 80% and 60% 30 days after primary vaccination, respectively. However, 30 days after booster vaccination, the protection level was 100%. At 60 days after secondary vaccination, the protection level dropped again to 80% for chickens vaccinated orally. All control chickens used in the challenge trials developed clinical ND and died 3-5 days after inoculation with the virulent virus. Supported by laboratory findings, I2 strain of NDV seemed to be avirulent, immunogenic and highly protective against virulent isolates of NDV. It may be a suitable vaccine to use in village chickens to vaccinate them against ND in rural areas. 相似文献
7.
新城疫病毒的进化及其新型疫苗的研制 总被引：3，自引：1，他引：2
新城疫病毒（NDV）虽然只有一个血清型,但其强毒已进化出现了九个基因型。近年来,ND疫苗在世界范围内得到了广泛使用,但免疫鸡群中ND强毒感染仍然常见。常用疫苗株LaSota对不同基因型的ND强毒流行株虽能产生完全的临床保护,但并不能防止流行株在免疫鸡中的感染复制和排出。国内外研究结果显示：当疫苗株与流行株的基因型一致时,其不仅能提供理想的临床保护,而且能显著降低免疫鸡的强毒感染率和排毒量,在临床上可有效控制免疫鸡群中非典型ND的发生。当前我国NDV的优势流行株属基因VII型,因此该型ND疫苗在控制我国ND的流行中将具有非常广阔的应用前景。 相似文献
8.
本研究以新城疫病毒(NDV)V蛋白羧基端结构域(Vc)的重组蛋白为包被抗原,建立了用于检测NDV V蛋白抗体的间接ELISA方法,并采用该方法检测了鸡群免疫或接毒后血清中的V蛋白抗体水平。结果显示:两组不同NDV灭活疫苗组在免疫后的3周内检测结果均为阴性;两组灭活疫苗免疫3周后再人工感染NDV强毒的鸡群,攻毒后第7、14和21 d,NDV阳性率分别为60%、80%、70%和50%、80%、70%;两组不同的NDV弱毒疫苗免疫组鸡群,仅在免疫后第21 d阳性率分别为20%和10%。以上结果表明,NDV疫苗免疫组与强毒感染组的V蛋白抗体阳性率存在明显差异,本方法可在群体水平上区分新城疫疫苗免疫与强毒感染鸡群,为NDV血清学诊断和流行病学调查提供了一种新的检测手段。 相似文献
9.
Generation of a genotype VII Newcastle disease virus vaccine candidate with high yield in embryonated chicken eggs 总被引：1，自引：0，他引：1
To generate a genotype VII Newcastle disease virus (NDV) vaccine with high yield in embryonated chicken eggs, we selected genotype VII NDV strain JS5/05, which possesses a high virus titer in embryos as the parental virus. Using reverse genetics, we generated a genetically tagged derivative (NDV/AI4) of JS5/05 by changing the amino acid sequence of the cleavage site of the F0 protein. Pathogenicity tests showed that NDV/AI4 was completely avirulent. NDV/AI4 was genetically stable and replicated efficiently during 10 consecutive passages in embryos. More importantly, serologic assays showed that oil-emulsion NDV/AI4 induced higher hemagglutination inhibition (HI) titers against the prevalent virus than oil-emulsion LaSota vaccine in chickens and geese. Moreover, NDV/AI4-induced HI titers rose faster than those elicited by LaSota in chickens. Both NDV/AI4 and LaSota provided protection against clinical disease and mortality after the challenge with the genotype VII NDV strain JS3/05. However, NDV/AI4 significantly reduced virus shedding from the vaccinated birds compared to LaSota. Taken together, these results suggest that NDV/AI4 can provide better protection than LaSota and is a promising vaccine candidate against genotype VII NDV. 相似文献
10.
Wambura PN 《Tropical animal health and production》2009,41(2):149-152
The efficacy of green-coloured (GC) I-2 Newcastle disease vaccine was determined in the present study. I-2 vaccine was mixed
with a green coloured dye and stored at 4°C for 6 months while assayed for the virus infectivity at a monthly interval. Chickens
were vaccinated with the GC vaccine by eye drop. Serum samples were collected from all birds before and after vaccination
at weekly interval for 4 weeks and tested for haemagglutination-inhibition (HI) antibody against Newcastle disease virus (NDV). These chickens were challenged with NDV virulent strain four weeks after vaccination. The results showed that there
was no difference between the infectivity titres of GC and uncoloured vaccines. However, chickens vaccinated with GC vaccine
produced higher HI antibody titres than chickens vaccinated with uncoloured vaccine. Results from the challenge trial showed
that all vaccinated chickens survived whereas all unvaccinated chickens died. The findings from this study have shown that
the GC vaccine is safe and produced protective antibodies against NDV in vaccinated chickens.
Wambura, P. N., 2008. Protective antibody response produced by the chickens vaccinated with green coloured thermostable Newcastle
disease virus. Tropical Animal Health and Production. 相似文献
11.
Woo-Jin Jeon Eun-Kyoung Lee Young-Jeong Lee Ok-Mi Jeong Yong-Joo Kim Jun-Hun Kwon Kang-Seuk Choi 《Journal of veterinary science (Suw?n-si, Korea)》2008,9(3):295-300
Despite the intensive vaccination policy that has been put in place to control Newcastle disease virus (NDV), the recent emergence of NDV genotype VII strains in Korea has led to significant economic losses in the poultry industry. We assessed the ability of inactivated, oil-emulsion vaccines derived from La Sota or Ulster 2C NDV strains to protect chickens from challenge with Kr-005/00, which is a recently isolated Korean epizootic genotype VII strain. Six-week-old SPF chickens were vaccinated once and challenged three weeks later via the eye drop/intranasal route. All vaccinated birds were fully protected from disease, regardless of the vaccine strains used. All vaccinated and challenged groups showed significant sero-conversion 14 days after challenge. However, some vaccinated birds, despite being protected from disease, shed the challenge virus from their oro-pharynx and cloaca, albeit at significantly lower titers than the unvaccinated challenged control birds. The virological, serological, and epidemiological significance of our observations with regard to NDV disease eradication is discussed. 相似文献
12.
Youn-Jeong Lee Haan-Woo Sung Jun-Gu Choi Eun-Kyoung Lee Hachung Yoon Jae-Hong Kim Chang-Seon Song 《Journal of veterinary science (Suw?n-si, Korea)》2008,9(3):301-308
Recombinant baculoviruses containing the fusion (F) and hemagglutinin-neuraminidase (HN) glycoprotein gene of the viscerotropic velogenic (vv) Newcastle disease virus (NDV) isolate, Kr-005/00, and a lentogenic La Sota strain of the NDV were constructed in an attempt to develop an effective subunit vaccine to the recent epizootic vvNDV. The level of protection was determined by evaluating the clinical signs, mortality, and virus shedding from the oropharynx and cloaca of chickens after a challenge with vvNDV Kr-005/00. The recombinant ND F (rND F) and recombinant HN (rND HN) glycoproteins derived from the velogenic strain provided good protection against the clinical signs and mortality, showing a 0.00 PI value and 100% protection after a booster immunization. On the other hand, the combined rND F + HN glycoprotein derived from the velogenic strain induced complete protection (0.00 PI value and 100% protection) and significantly reduced the amount of virus shedding even after a single immunization. The rND F and rND HN glycoproteins derived from the velogenic strain had a slightly, but not significantly, greater protective effect than the lentogenic strain. These results suggest that the combined rND F + HN glycoprotein derived from vvNDV can be an ideal subunit marker vaccine candidate in chickens in a future ND eradication program. 相似文献
13.
应用电镜技术、血清学检查、生物学试验等方法,从未注射过疫苗的某自然发病鸡群分离出一株新城疫病毒。该分离株对１０日龄鸡胚的平均致死时间为１１６小时,静脉接种致病指数为０．０６,其毒力介于新城疫病毒的ＬａＳｏｔａ株与Ｖ４株之间。免疫原性试验结果表明,该分离株具有免疫后无不良反应、免疫后６天开始产生抗体、产生的抗体效价高、对新城疫强毒的攻击能１００％保护等特点,是一株良好的新城疫候选疫苗株 相似文献
14.
Shafqat F. Rehmani 《Preventive veterinary medicine》1996,25(3-4):241-248
Twelve-day-old chickens were vaccinated once with different Newcastle disease (ND) vaccines ( F, La Sota and Mukteswar) by two different routes (intraocular and drinking water). Chickens from a seventh group were uninoculated controls. At weekly intervals for 7 weeks after vaccination, 20 chickens from each vaccinated group and 20 chickens from the control group were examined for the production of haemagglutination-inhibition (HI) antibodies and for protection as assessed after challenge with velogenic, viscerotropic ND virus.
La Sota ND vaccine used intraocularly ranked the best and Mukteswar vaccine by the drinking water route the worst for their HI antibody titres prior to challenge. Differences between the treatments in protection were examined. For all three vaccines intraocular vaccine produced higher protection than drinking water vaccine. An inverse relationship between prechallenge and postchallenge HI titres was also recorded. 相似文献
15.
Kiarash Roohani Sheau Wei Tan Swee Keong Yeap Aini Ideris Mohd Hair Bejo Abdul Rahman Omar 《Journal of veterinary science (Suw?n-si, Korea)》2015,16(4):447-457
A Newcastle disease virus (NDV) isolate designated IBS002 was isolated from a commercial broiler farm in Malaysia. The virus was characterised as a virulent strain based on the multiple basic amino acid motif of the fusion (F) cleavage site 112RRRKGF117 and length of the C-terminus extension of the hemagglutinin-neuraminidase (HN) gene. Furthermore, IBS002 was classified as a velogenic NDV with mean death time (MDT) of 51.2 h and intracerebral pathogenicity index (ICPI) of 1.76. A genetic distance analysis based on the full-length F and HN genes showed that both velogenic viruses used in this study, genotype VII NDV isolate IBS002 and genotype VIII NDV isolate AF2240-I, had high genetic variations with genotype II LaSota vaccine. In this study, the protection efficacy of the recombinant genotype VII NDV inactivated vaccine was also evaluated when added to an existing commercial vaccination program against challenge with velogenic NDV IBS002 and NDV AF2240-I in commercial broilers. The results indicated that both LaSota and recombinant genotype VII vaccines offered full protection against challenge with AF2240-I. However, the LaSota vaccine only conferred partial protection against IBS002. In addition, significantly reduced viral shedding was observed in the recombinant genotype VII-vaccinated chickens compared to LaSota-vaccinated chickens. 相似文献
16.
King DJ 《Avian diseases》1999,43(4):745-755
Four-week-old specific-pathogen-free white rock chickens were immunized with either a commercial recombinant fowl poxvirus-vectored Newcastle disease vaccine (FPN) expressing the hemagglutinin-neuraminidase and fusion protein genes of Newcastle disease virus (NDV) strain B1 or live NDV B1. Vaccinates and controls were challenged by eyedrop and intranasal (E/I) route with a viscerotropic velogenic NDV at 14 days postvaccination to determine the time of clearance of challenge virus. In a subsequent experiment, chickens were challenged at 3, 6, or 10 days postvaccination to determine the onset of immunity. Chickens that received a recommended field dose (1x) or a 0.01x dose of FP-N subcutaneously (s.c.) and were seropositive by hemagglutination-inhibition test at 14 days postvaccination cleared the challenge virus by 14 days postchallenge. Clinical Newcastle disease and high challenge virus titers in tissues were seen only in seronegative FP-N 0.01x dose vaccinates and controls. In a comparison of vaccination with FP-N (1x, 10(4,9) median tissue culture infective dose) s.c., B1 (10(6) median egg infective dose [EID50]) s.c., or B1 (10(6) EID50) E/I, chickens vaccinated at 6 or 10 days before challenge with all vaccines were protected against clinical disease, but only those vaccinated with B1 E/I 10 days before challenge were protected against infection with the challenge virus. Vaccination at 3 days before challenge with B1 E/I provided early protection, but severe nervous signs developed later and reduced overall protection to 60%, whereas disease in chickens vaccinated with B1 s.c. and FP-N s.c. 3 days before challenge was similar to the challenge controls. 相似文献
17.
A recombinant fowlpox virus (rFPV) coexpressing the Newcastle disease virus (NDV) fusion and hemagglutinin-neuraminidase genes and infectious laryngothracheitis virus (ILTV) glycoprotein B gene was constructed. This virus was then evaluated for its ability to protect specific-pathogen-free (SPF) chickens against clinical symptoms and death after challenge by virulent NDV and ILTV. SPF chickens were grouped and vaccinated with the rFPV and commercial NDV (La Sota) and ILTV attenuated live vaccine (Nobilis ILT), respectively. After challenge with NDV 10 days postvaccination, 70% of chickens vaccinated with rFPV were protected from death, whereas 100% of the commercial NDV-vaccinated chickens were protected from death. In contrast, 100% of the unvaccinated chickens died after challenge. After challenge with ILTV, both the rFPV and commercial ILTV-vaccinated chickens were completely protected from death and 70% of chickens were protected from respiratory signs. In comparison, 100% of the unvaccinated chickens developed severe respiratory disease and 10% of chickens died. The protective efficacy was also measured by the antibody responses and isolation of challenge viruses. Results showed that this rFPV could be a potential vaccine for preventing NDV and ILTV by a single immunization. 相似文献
18.
Meat chickens on commercial broiler farms were vaccinated once at 1 to 15 days of age with a live V4 Newcastle disease virus (NDV) vaccine administered by drinking water, aerosol or coarse spray. Hatchmates were housed and similarly vaccinated in laboratory isolation pens. Samples of birds were bled at weekly to fortnightly intervals and the serums tested for haemagglutination inhibiting antibody to NDV. Log2 mean titres of up to 6.26, and assumed protection levels (based on the percentage of birds with log2 titres of 4 or greater) of up to 89%, were obtained in field trials within 4 weeks of vaccination. Differences were observed between the results obtained from parallel field and laboratory trials. The presence of maternal NDV antibody reduced the response to vaccination. The results show that this V4 vaccine can produce an adequate serological response following mass administration to Australian meat chickens housed under commercial conditions. 相似文献
19.
Vaccination of chickens using raw rice coated with novel trehalose nano-organogels containing Newcastle disease (strain I-2) vaccine 总被引：1，自引：1，他引：0
P. N. Wambura 《Tropical animal health and production》2009,41(5):797-802
The formulation and evaluation of trehalose nano-organogels for storage and oral delivery of Newcastle disease (ND) strain
I-2 vaccine to chickens were carried out in this study. Trehalose sugar was blended with vegetable oil to form nano-organogels
where trehalose also acted as a stabilizer against thermal inactivation of I-2 ND virus. Results from infectivity titration
assay indicated that the titre of 107.5 EID50/0.1 mL was maintained after 12 weeks of storage of nano-organogel I-2 vaccine at ambient room temperature. Serology results
showed that 33% chickens which were vaccinated with nano-organogel I-2 vaccine after 14 days had HI antibody titres of ≥ 3.0 log2 with GMT of 2.3. Moreover, results showed 100% of chickens vaccinated with nano-organogel I-2 vaccine had the mean antibody
titres of 3.4 and 3.7 log2 at 21 and 28 days after vaccination, respectively. All vaccinated chickens (100%) survived the challenge of virulent ND virus
whereas all unvaccinated chickens succumbed to challenge and died of signs consistent with ND. The findings from this study
showed that the nano-organogel I-2 vaccine was stable at room temperature, safe and produced protective antibody response
in vaccinated chickens. Moreover the nano-organogel I-2 vaccine was used for oral administration and hence is suitable for
mass vaccination. However, optimization of the formulation of trehalose nano-organogel vaccine is required in order to achieve
its application potentials. 相似文献
20.
Singh Rajinder Verma Prem C. Singh Satparkash 《Tropical animal health and production》2010,42(3):465-471
Virosome based vaccines against Newcastle disease (ND) were prepared and evaluated for their immunogenicity and protective
efficacy in chickens. Envelop of Newcastle disease virus (NDV) was solubilised with Triton X-100 to yield virosomes which
were later on encapsulated in poly-lactide-co-glycolide (PLG) microspheres. The birds were immunized intranasally with virosomes
or PLG microspheres encapsulated virosomes, and efficacy of these preparations was compared with commercial LaSota vaccine.
The preparations protected the chickens against virulent virus challenge infection, however the microencapsulated virosome
vaccine gave slightly lesser degree of protection than non encapsulated counterpart. The humoral and cell mediated immune
response generated as well as the protection afforded by virosome preparations were found to be comparable with LaSota vaccine.
The results substantiate the potential of virosome based vaccines to provide high level of immunity and protection against
Newcastle disease. 相似文献