• Korean Journal of Veterinary Research
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• v.49 no.1
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• pp.39-44
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• 2009

Transmission of avian viruses both bird-to-bird and from birds to non-avian species is a major health concern. Newcastle disease virus (NDV) is an economically important avian virus that poses substantial risks to the poultry industry. Rapid and sensitive diagnostic methods, such as the enzymelinked immunosorbent assay (ELISA), are required to track such infections. To develop an ELISA for detecting anti-NDV antibody in avian sera, the nucleocapsid protein (NCP) gene of the NDV La Sota strain was cloned and expressed in Escherichia coli and the 513-amino acid recombinant NCP was purified by Ni-NTA affinity chromatography. To evaluate its ability to replace NDV whole virus antigen as a coating antigen, NCP-coated and whole NDV-coated ELISAs were tested and compared using a panel of NDV positive antisera from chickens. Results using purified NCP were highly correlated with those obtained using whole NDV (r= 0.927), demonstrating that recombinant NCP expressed in Escherichia coli is a suitable substitute antigen for whole NDV in a diagnostic ELISA.

• Journal of Veterinary Science
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• v.21 no.2
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• pp.19.1-19.10
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• 2020

Given that the current Newcastle disease virus (NDV) infection in wild birds poses the threat to poultry, surveillance of Newcastle disease in captive wild birds was carried out in Jilin, China in 2018. Here, an NDV strain obtained from toco toucan was firstly characterized. The results showed that the F gene of the NDV isolate Toucan/China/3/2018 is classified as genotype II in class II. Sequence analysis of the F0 cleavage site was ¹¹³RQGR/L¹¹⁷, which supports the result of the intracerebral pathogenicity index assay indicating classification of the isolate as low-pathogenicity. Experimental infection demonstrated that Toucan/China/3/2018 can effectively replicate and transmit among chickens. To our knowledge, this is the first report on genetically and pathogenically characterizing NDV strain isolated from toucan, which enriches the epidemiological information of NDV in wild birds.

• Korean Journal of Veterinary Service
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• v.21 no.2
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• pp.133-139
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• 1998

Serum samples collected from 30 breeders and their progeny 30 chicks. The antibodies against infectious bronchitis(IB), infectious bursal disease (IBD) and Newcastle disease(ND) viruses were detected by ELISA using commercial ELISA kit. The breeders were vaccinated against IB, IBD and ND viruses according to general vaccination program. Geometric mean titers(GMT) of ELISA were monitored from 1-day old to 17-day old chicks and compared with breeder chickens. The GMT of ELISA to IB, IBD and ND were declined half level of the breeder antibody titer at 6-, 8- and 7-day old. And, the GMT of ELISA to IB, IBD and ND were declined than that of protective titer at 6-, 1-, and 4-day old. Thereafter, the GMT of ELISA was declined and disappeared according to ages of chicks. Taken together, this study led to conclusion that time-course of maternal antibody titers of chicks from vaccinated breeders, and this is very important data for vaccination to chicks.

• Korean Journal of Veterinary Research
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• v.42 no.3
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• pp.351-362
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• 2002

Newcastle disease (ND) is a highly contagious infection of poultry, Two pathology-based techniques, in situ RT-PCR and in situ hybridization (ISH) were applied to formalin-fixed, paraffin-embedded tissues from chickens naturally infected with velogenic ND virus (VNDV). Two pairs of primers and a probe for ISH and in situ RT-PCR, respectively, were selected from highly conserved region of matrix gene of NDV. The ISH experiment was carried out using MicroProbe$^{TM}$ capillary action system within 2 hours. In situ RT-PCR was performed using MicroProbe$^{TM}$ capillary action system and GeneAmp In Situ PCR system. With ISH and in situ RT-PCR, viral nucleic acid was detected in the central nervous system of chickens from infected with neurotropic velogenic Newcastle disease virus (NVNDV), whereas viral nucleic acid was detected in various organs or tissues of chickens from infected with viscerotropic velogenic Newcastle disease virus (VVNDV). In the NVND group, positive signals were characteristically defined in the cytoplasm of neuron, vascular endothelial cells, and perivascular mononuclear macrophages in the central nervous system. One of NVND group, chicken from one farm exhibited positive signals in the bronchial epithelium. The VVND group chickens showed positive reaction in the macrophages, vascular endothelium, and bronchiolar epithelium. Markedly, viral nucleic acid was detected in the macrophages of morphologically normal tissues which were peripheral or located in distant areas from lesions. The central nervous system of chickens infected with VVND virus had positive signals in the vascular endothelial cell, perivascular mononuclear macrophages and some neuron. The number and intensity of the positive cells by in situ RT-PCR were more and stronger, respectively, in comparison with those by ISH. Particularly, positive reaction was detected in macrophages infiltrating in cardiac muscle by in situ RT-PCR, but not obtained by ISH. Therefore, these results demonstrated that ISH is a rapid diagnostic method for detection of NDV and in situ RT-PCR can be used as an efficient method for detection of low viral load infection or subclinical viral infection of NDV.

• Korean Journal of Poultry Science
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• v.19 no.2
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• pp.65-76
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• 1992

Since the first outbreaks of Newcastle disease ( ND) in Korea was reported in 1927, the disease has been a major problem in Korean poultry industry. Several attempts related ND prevention and controls have been tried and significantly reduced the ND outbreaks. However, recently frequencies of ND outbreaks have been increased throughout the country since 1988. Many assumptions such as variances of ND virus pathogenicity, decreased efficacy of ND vaccine, incorrect vaccination program etc, has been issued and discussed. Therefore, to clearly understand this recent situation of ND outbreaks in Korea, we reviewed all available past informations related with ND outbreaks in Korea and compared the virulence of recently isolated ND viruses with that of a reference one. Also, we discussed about some problems related with serological diagnosis. administration methods of vaccine and vaccination program.

• Korean Journal of Veterinary Service
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• v.15 no.2
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• pp.184-194
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• 1992

This study was done to identify Newcastle disease virus(NDV) antigens in paraffin sections of various organs from experimentally NDV-infected chicken using peroxidase-antiperoxidase(PAP) technique. Sections were Incubated with rabbit anti-NDV polyclonal as first antibody, followed by incubation with goat anti-rabbit IgG conjugate and peroxidase anti-peroxidase ( PAP ). Positive reactions were often detected in the epithelim of trachea and in the lymphocyte of spleen at 24 hours after virus inoculation. The viral antigen was localized mainly in the cytoplasm of infected cells. The method approved to be highly specific for the indetification of NDV and allowed a precise localization of the viral antigens in infected cells.

• Korean Journal of Veterinary Service
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• v.34 no.1
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• pp.19-29
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• 2011

Prevalence of major legal communicable diseases in chickens and ducks, which had occurred in Jeonbuk province from year 2004 to 2008. Total 283 farms 1,419,244 chickens and ducks have been affected by avian diseases. Specifically, fowl typhoid (FT) occurred in 92 farms 416,600 chickens, Marek's disease (MD) in 45 farms 145,563, duck virus hepatitis (DVH) in 31 farms 199,200, infectious bursal disease (IBD) in 27 farms 113,220, infectious bronchitis (IB) in 27 farms 280,300, low pathogenic avian influenza (LPAI) in 26 farms 78,495, avian mycoplasmosis in 16 farms 103,774, Newcastle disease (ND) occurred in 11 farms 61,052, avian encephalomyelitis (AE) in 7 farms 21,000, Pullorum disease (PD) occurred in 1 farm 40. According to total analysis about major legal communicable diseases, 1 species of first-class legal communicable diseases have occurred, 3 species of second-class and 6 species of third-class all adding up to 10 species. In the first-class diseases, Newcastle disease have occurred. Pullorum and fowl typhoid, duck virus hepatitis in the second-class have occurred and as third-class diseases, Marek's disease, Infectious bursal disease, Infectious bronchitis, avian mycoplasmosis, avian encephalomyelitis, low pathogenic avian influenza have occurred.

• Journal of the korean veterinary medical association
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• v.9 no.3
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• pp.13-17
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• 1965

• Journal of the korean veterinary medical association
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• v.5 no.1
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• pp.39-40
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• 1961

• Proceedings of the KSAR Conference
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• 2002.06a
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• pp.189.1-189
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• 2002