Our study demonstrates the repeated isolation of vaccine-derived Newcastle disease viruses from different species of wild birds across four continents from 1997 through 2014. The data indicate that at least 17 species from ten avian orders occupying different habitats excrete vaccine-derived Newcastle disease viruses. The most frequently reported isolates were detected among individuals in the ...

Avian influenza viruses of the H5 and H7 hemagglutinin subtypes, and Newcastle disease virus (NDV), are important pathogens in poultry worldwide. Specifically, the highly pathogenic H5N1 avian influenza virus is a particular threat because it has now occurred in more than 40 countries on several continents. Inasmuch as most chickens worldwide are vaccinated with a live NDV vaccine, we embarked ...

Frequent vaccination failures have occurred in the broiler farms in Eurasian countries during Newcastle disease outbreaks. The disease is enzootic in many countries of the region, especially in southwest Asia. I-2 vaccine has been used successfully in village chickens in many Asian and African countries. Our preliminary study showed good efficacy of the vaccine in broiler chickens. Therefore th...

Current vaccination strategies for commercial poultry using live attenuated and inactivated Newcastle disease (ND) vaccines have some limitation and difficulties, and new vaccines with distinct features are needed. Recently, in ovo vaccination technology is concerned as a safe, efficacious, and convenient method. Common ND vaccines used in chickens cannot be employed in ovo due to embryo toxici...

background and aims: the objective of this study was to investigate the effects of newcastle disease and infectious bronchitis vaccination programs in chickens. materials and methods and results: in the present study, 225 day-old broiler chicks divided into 5 groups. the groups were submitted to vaccinations, except for the non-vaccinated control group. the chickens in the groups 1 were kept as...

background & aim: the recent study was conducted to investigate the effects of thyme extract in drinking water on immune response of broiler chickens. experimental:  a total of 245 day-old broiler chicks were purchased and 20 chicks were bled for determination maternal antibody and remaining chicks divided into 5 equal groups. chickens of group a, b and c received 0.1%, 0.15% and 0.2% ofthy...

newcastle disease is one of the most important causes of economic losses in the poultry production and can be resulted in high mortality. antibody detection is also an important tool for assessment of the immunity against the disease. in the present study a trial was conducted to evaluate the effect of an immune stimulator (echinacea purpurea) on antibody production against newcastle disease va...

Newcastle disease virus (NDV) strain F is a lentogenic vaccine strain used for primary vaccination in day-old chickens against Newcastle disease (ND) in India and Southeast Asian countries. Recombinant NDV-F virus and another recombinant NDV harboring the major capsid protein VP2 gene of a very virulent infectious bursal disease virus (IBDV); namely rNDV-F and rNDV-F/VP2, respectively, were gen...