Avian influenza (AI) is a highly contagious disease causing significant economic losses worldwide. The aim of this study is to evaluate the effect of mannan-oligosaccharide (MOS) on tracheal and cloacal virus shedding in AI challenged broilers and contamination of environment with H9N2. A total of 300 1-day-old-broiler chicks were randomly divided into 3 groups (A, B and C) and supplemented 0.2...

We investigate the protective effect of combined vaccination based on live attenuated influenza vaccine (LAIV) and group B streptococcus (GBS) recombinant polypeptides against potential pandemic H7N9 influenza infection followed by GBS burden. Mice were intranasally immunized using 107 50% egg infectious dose (EID50) of H7N3 LAIV, the mix of the 4 GBS peptides (group B streptococcus vaccine [GB...

Although Newcastle disease virus (NDV) with high pathogenicity has frequently been isolated in poultry in China since 1948, the mode of its transmission among avian species remains largely unknown. Given that various wild bird species have been implicated as sources of transmission, in this study we genotypically and pathotypically characterized 23 NDV isolates collected from chickens, ducks, a...

A series of experiments was carried out in hamsters to determine their value as an experimental animal for the study of influenza virus infection and immunization. Hamsters could be infected intranasally with approximately 100 EID50 of unadapted influenza A/Port Chalmers/73 virus; infection produced serum HI antibody and virus was recovered from both nasal washings and from lungs. Inoculation o...

Forty-two, one-day-old specific pathogen-free (SPF) chickens were randomly divided into two groups. On 21st day of study, experimental group was infected intraocularly with 1×106 EID50 of H9N2 and intratracheally with 1× 1010 CFU of Ornithobacterium rhinotracheale (ORT). Control group was inoculated with sterile PBS intraocularly. The samples from various tissues were collected on days 2, 4, 6,...

Using peptide nanoparticle technology, we have designed two novel vaccine constructs representing M2e in monomeric (Mono-M2e) and tetrameric (Tetra-M2e) forms. Groups of specific pathogen free (SPF) chickens were immunized intramuscularly with Mono-M2e or Tetra-M2e with and without an adjuvant. Two weeks after the second boost, chickens were challenged with 107.2 EID50 of H5N2 low pathogenicity...

Background: The H9N2 subtype of the influenza virus, which is endemic in many regions of Iran, is considered as a candidate for future pandemics. In the present study, excretion time of the Iranian endemic influenza virus (H9N2 subtype) from the feces and pharyngeal secretions of laying chicken breeds was evaluated. Methods: This experimental study conducted at the Diagnostic Laboratory Scienc...

Avian influenza outbreaks in 1998 due to H9N2 subtype of avian influenza virus (AIV) that occurred in poultry industry in Iran caused serious economic losses. The aim of this study was to investigate the pathogenesis, clinical signs, gross and histopathological findings of the chickens experimentally inoculated with A/Chicken/Iran/772/99(H9N2) influenza virus, isolated from the commercial broil...

We analyzed five H5N1 avian influenza viruses (AIVs) isolated from different birds in 2012 in China. Based on whole-genome sequences, we divided the viruses into four genotypes. The DKE26, GSE43, and DKE53 viruses belonged to Genotypes 1-3, respectively. The CKE93 and CKE96 viruses were classified into Genotype 4. Genotypes 1-3 correspond to the viruses containing the HA gene of clade 2.3.2, an...

Mukteswar strain of Newcastle disease (ND) virus was propagated in 9-day-old embryonated eggs via allantoic route. The harvested allantoic fluid with haemagglutination (HA) titre of 1024 (EID50 10) was inactivated using 0.1 percent formalin solution. Two experimental vaccines were prepared in light mineral oil with aqueous to oil ratio of 1:2 ( MK-VAC-I) and 1:4(MK-VAC-II).The hydrophile lipoph...