The present study has been designed to investigate of infectious bronchitis virus (IBV).is a widely distributed poultry disease that large economic impact on industry. Infections the respiratory, reproductive, and renal systems are caused by IBV. avian immune system is capable activating mucosal, humoral, cell-mediated immunity in response future antigen exposure. Currently, live attenuated kil...

Infectious bronchitis virus (IBV) is prevalent in all countries with an intensive poultry industry, with the incidence of infection approaching 100% in most locations. Vaccination is only partially successful due to the continual emergence of antigenic variants. At many sites, multiple antigenic types are simultaneously present, requiring the application of multiple vaccines. Although many coun...

Background and Aims: Newcastle disease (ND) is a highly contagious disease in poultry with economic losses in the world. Vaccination is one of the most important ways for prevention and control of NDV, but there are reports of ND outbreaks in vaccinated chickens. Poor quality of the vaccines is one of the reasons of vaccine failure. In this study the quality of two commercial oil-emulsion Newca...

This paper describes two experiments. In each experiment, 1-day-old specific pathogen free chicks were divided into three groups. In Experiment 1 - [avian metapneumo virus (aMPV) challenge] - one group served as unvaccinated controls; the second group was vaccinated with live aMPV (subtype B) vaccine only, and the third group received the aMPV vaccine in combination with live Newcastle disease ...

In this study Mentofin was used in commercial broiler chickens naturally exposed to infectious bursal disease virus (IBDV) and administered live Newcastle disease virus (NDV) vaccine to evaluate the ability of Mentofin to reduce Escherichia coli-related respiratory lesions, immunomodulate Newcastle disease (ND) vaccine response, change pharyngeal aerobic bacterial counts, and have certain impac...

The experiment aimed to study the effect of post-hatch early held feeding times starter supplemented with egg yolk and white on growth performance, viscera development and immune response in broiler chickens. The working hypothesis was based on the fact that better development of the gastrointestinal tract and immunity system in the first week of the chicks' life affects positively the growth p...

Due to variations in serotypes among different strains of avian infectious bronchitis viruses (IBV), vaccination of chicks with imported vaccines fails to protect them from IBV infections in Taiwan. Therefore, we develop attenuated vaccines from local strains in Taiwan. A Taiwan Group I (TW I) strain was passaged 74 times through specific pathogen-free (SPF) chicken embryonated eggs, and then t...

OBJECTIVE To monitor and study the molecular epidemiology, evolution and pathogenicity of infectious bronchitis viruses (IBVs) in China in recent years and further our knowledge of the evolution of IBVs. METHODS Thirty-seven IBV isolates were isolated from commercial chickens in China. The isolates were characterized by RT-PCR, sequencing, typing and analyzing the entire S1 gene. In addition,...

Infectious bronchitis virus (IBV) infections cause great economic losses to the poultry industry worldwide, and the emergence of new variant strains complicates disease control. The present study investigated the genetic and protectotypic features of newly emerged Korean IBV strains. A phylogenetic analysis showed that several recent isolates formed 2 different clusters (new cluster 1 and 2), w...