Avian infectious bronchitis is an acute and highly contagious disease that mainly causes respiratory symptoms in poultry. A number of serotypes and variants of the viral agent with poor cross-protection are the major problem to achieve desired immunity from vaccination. The S1 subunit of S glycoprotein (spike) is the major determinant of IBV so that a minor change in amino acid sequence of this...

We have previously demonstrated that the replacement of the S gene from an avirulent strain (Beaudette) of infectious bronchitis virus (IBV) with an S gene from a virulent strain (M41) resulted in a recombinant virus (BeauR-M41(S)) with the in vitro cell tropism of the virulent virus but that was still avirulent. In order to investigate whether any of the other structural or accessory genes pla...

avian infectious bronchitis is an acute and highly contagious disease that mainly causes respiratory symptoms in poultry. a number of serotypes and variants of the viral agent with poor cross-protection are the major problem to achieve desired immunity from vaccination. the s1 subunit of s glycoprotein (spike) is the major determinant of ibv so that a minor change in amino acid sequence of this...

Chicken infectious bronchitis virus (IBV) causes severe respiratory and renal dysfunction in chickens. In the present study, we used reverse transcription-polymerase chain reaction (RT-PCR) to amplify the nucleocapsid (N) protein gene of strain Massachusetts (Mass) H120 of IBV that is commonly used in the vaccine production in Iran. The PCR product with the expected size of 1.2 kb was cloned in...

background: the purpose of this study was to find out the frequency of different serotypes of enteropathogenic es­cherichia coli (epec) among healthy/diarrheal cases. methods: a total of 191 strains, 111 from diarrheal and 80 from asymptomatic persons were examined. determination of the epec sero­groups was performed by agglutination tests using polyvalent and monovalent o antiserum. pcr-rflp a...

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,...

Salmonella is one of the most important zoonotic pathogens with many virulence factors playing a major role in its pathogenesis. The aims of this study were to detect spvA, int2 and invC virulence genes of different Salmonella serotypes isolated from various clinical animal and human sources, and to investigate antibiotic resistance patterns among these serotypes. Using a PCR assay, a total of ...

Avian infectious bronchitis (IB), caused by a gammacoronavirus, is an OIE-listed (List B) disease and characterized by respiratory and renal involvements, causing high mortality, and economic loss in both layers and broilers. In comparison with other diagnostic methods, real-time polymerase chain reaction (RT-PCR) and conventional RT-PCR are potent, more sensitive and faster techniques for infe...

Inactivated oil-adjuvanted vaccines for ND, IB, and IC serotypes A and C (OILVAX NB2AC) have been marketed from 1993. In the outdoors, various inoculation sites have been used in chickens because to make the inoculation procedure easier. We examined whether differences would be obtained in the antibody response according to the inoculation sites; the subcutaneous inoculation into the back of th...