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 virus (NDV) causes a devastating poultry disease worldwide. Frequent outbreaks of NDV in chickens vaccinated with conventional live vaccines suggest a need to develop new vaccines that are genetically matched against circulating NDV strains, such as the genotype V virulent strains currently circulating in Mexico and Central America. In this study, a reverse genetics system was...

Different infectious bursal disease virus (IBDV) live vaccines (intermediate, intermediate plus) were compared for their immunosuppressive abilities in specific-pathogen-free (SPF) layer-type chickens or commercial broilers. The Newcastle disease virus (NDV) vaccination model was applied to determine not only IBDV-induced immunosuppression but also bilateral effects between IBDV and NDV. None o...

The control of Newcastle disease (ND) in South Africa has proved difficult since 2002 following the introduction of lineage 5d/VIId Newcastle disease virus (NDV) strain ("goose paramyxovirus" - GPMV) to which commercially available ND vaccines appeared less effective. Most of the ND infections, even in fully vaccinated hens were characterized consistently by a drop in egg production. In this st...

Background: Newcastle disease virus (NDV) genotype VII has become the dominant genotype in China. However, NDV genotype II was used to make current commercial NDV vaccines. The mismatch of genotypes between circulating and vaccine strains of viruses may compromise the efficacy of vaccines. Methods: In this study, a current circulating NDV was attenuated by mutations of multiple basic amino acid...

Newcastle disease (ND) is a highly contagious disease of chickens causing significant economic losses worldwide. Due to limitations in the efficacy against currently circulating ND viruses, existing vaccination strategies require improvements, and incorporating immunomodulatory cytokines with existing vaccines might be a novel approach. Here, we investigated the systemic and mucosal immunomodul...

Title of Document: ROLE OF NONCODING REGIONS IN NEWCASTLE DISEASE VIRUS REPLICATION AND PATHOGENESIS Yongqi Yan, Doctor of Philosophy, 2008 Directed By: Professor Siba K.Samal College of Veterinary Medicine The roles of the intergenic sequences (IGS) and untranslated regions (UTR) in Newcastle disease virus (NDV) transcription and pathogenesis are not clear. By our established reverse genetics ...

Plasmid DNA (pDNA)-based vaccines have emerged as effective subunit vaccines against viral and bacterial pathogens. In this study, a DNA vaccine, namely plasmid internal ribosome entry site-HN/F, was applied in ovo against Newcastle disease (ND). Vaccination was carried out using the DNA vaccine alone or as a mixture of the pDNA and dextran-spermine (D-SPM), a nanoparticle used for pDNA deliver...