Commercial ELISA kits are commonly used to assess the levels of chicken antibodies against NewCastle Disease Virus (NDV) and trace a field strain infection. Nevertheless, the specificity of these kits vis-à-vis e...Commercial ELISA kits are commonly used to assess the levels of chicken antibodies against NewCastle Disease Virus (NDV) and trace a field strain infection. Nevertheless, the specificity of these kits vis-à-vis endemic strains in Lebanon remains in question. This study developed an in-house indirect ELISA system to evaluate the level of chicken antibodies against a predominant velogenic NDV strain belonging to Genotype VI. A checkerboard analysis comprised a five-factorial multivariate experiment to optimize the protocol: coating antigen concentration, blocking buffer utilization, serum and conjugate dilution levels, and OD reading wavelength. The developed test was optimized and then validated through parallel testing of the sera of 20 broilers and 5 layers using standard serological assays. There was a strong correlation between the developed ELISA results and those obtained with the Hemagglutination Inhibition test (P < 0.01), and a commercial NDV ELISA kit (P < 0.05). The specificity, sensitivity, and reproducibility of the developed ELISA suggest that it can be used as the test of choice for the assessment of chicken antibody titers against locally circulating velogenic NDV strains, specifically those belonging to Genotype VI. It also offers better help in the serological detection of birds’ exposure to the said strains.展开更多
[ Objective]This study aimed to compare differences in the pathogenicity between genotype VI Newcastle disease virus （NDV） strains from pigeons and chickens in pigeons. [ Method] Two-month-old pigeons were artificia...[ Objective]This study aimed to compare differences in the pathogenicity between genotype VI Newcastle disease virus （NDV） strains from pigeons and chickens in pigeons. [ Method] Two-month-old pigeons were artificially inoculated with ZJ3 strain from chickens and WX-10-07-Pi strain from pigeons. After inoc- ulation, the clinical symptoms, pathological anatomical changes, tracheal and cloacal detoxification, and histological lesions of experimental pigeons were observed. [ Result] Both ZJ3 strain and WX-10-07-Pi strain could infect pigeons with the incidence rate of 100%, but the mortality rate was 0. The cloacal detoxification time of pigeons in WX-10-07-Pi infection group was longer, and the virus detection rate was higher; in addition, the virus could be detected in various tissues and organs of inoculated pigeons. [ Conclusion] Different genotypes of NDV are pathogenic to pigeons, but the pathogenicity is related to the features of NDV strains. Genotype VIb NDV from pigeons can be carried and discharged for a long term in pigeons, which can spread in pigeon groups more easily.展开更多
文摘Commercial ELISA kits are commonly used to assess the levels of chicken antibodies against NewCastle Disease Virus (NDV) and trace a field strain infection. Nevertheless, the specificity of these kits vis-à-vis endemic strains in Lebanon remains in question. This study developed an in-house indirect ELISA system to evaluate the level of chicken antibodies against a predominant velogenic NDV strain belonging to Genotype VI. A checkerboard analysis comprised a five-factorial multivariate experiment to optimize the protocol: coating antigen concentration, blocking buffer utilization, serum and conjugate dilution levels, and OD reading wavelength. The developed test was optimized and then validated through parallel testing of the sera of 20 broilers and 5 layers using standard serological assays. There was a strong correlation between the developed ELISA results and those obtained with the Hemagglutination Inhibition test (P < 0.01), and a commercial NDV ELISA kit (P < 0.05). The specificity, sensitivity, and reproducibility of the developed ELISA suggest that it can be used as the test of choice for the assessment of chicken antibody titers against locally circulating velogenic NDV strains, specifically those belonging to Genotype VI. It also offers better help in the serological detection of birds’ exposure to the said strains.
基金Supported by National Natural Science Foundation of China(31440083)Science and Technology Support Program of Jiangsu Province(BE2012366)Science and Technology Program of Jiangsu Agri-animal Husbandry Vocational College(YB201006)
文摘[ Objective]This study aimed to compare differences in the pathogenicity between genotype VI Newcastle disease virus （NDV） strains from pigeons and chickens in pigeons. [ Method] Two-month-old pigeons were artificially inoculated with ZJ3 strain from chickens and WX-10-07-Pi strain from pigeons. After inoc- ulation, the clinical symptoms, pathological anatomical changes, tracheal and cloacal detoxification, and histological lesions of experimental pigeons were observed. [ Result] Both ZJ3 strain and WX-10-07-Pi strain could infect pigeons with the incidence rate of 100%, but the mortality rate was 0. The cloacal detoxification time of pigeons in WX-10-07-Pi infection group was longer, and the virus detection rate was higher; in addition, the virus could be detected in various tissues and organs of inoculated pigeons. [ Conclusion] Different genotypes of NDV are pathogenic to pigeons, but the pathogenicity is related to the features of NDV strains. Genotype VIb NDV from pigeons can be carried and discharged for a long term in pigeons, which can spread in pigeon groups more easily.
