[Evaluation of the protection conferred by several avian infectious bronchitis attenuated vaccines against the field strain CK/CH/LDL/97 I in China].
The entire S1 protein gene of five infectious bronchitis (IB) vaccine strains (JAAS, IBN, Jilin, J9, H120) used in China were compared with that of the IB field isolate CK/CH/LDL/97 I present in China. The nucleotide and deduced amino acid similarities between the five IB vaccine strains and the field strain, CK/CH/LDL/97 I, were not more than 76.4% and 78.7%, respectively. Phylogenetic analysis based on the S1 gene showed that the vaccine strains and the field strain belonged to different clusters and had larger evolutionary distances, indicating that they were of different genotypes. The five vaccine strains were used for protection test against challenge of the field isolate CK/CH/LDL/97 I. The chickens inoculated with five vaccine strains showed morbidity as high as 30%-100% after challenged with the CK/CH/ LDL/97 I strain. The organ samples at 5 days post challenge showed that the viral detection rates were 50%-90% and 10%-30% for trachea and kidney, respectively. The live attenuated vaccines only provided partial protection to the vaccinated chickens against heterologous IBV infection, CK/CH/LDL/97 I.
Division of Avian Infectious Diseases, National Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute of Chinese Academy of Agricultural Sciences, Harbin 150001, Heilongjiang, China.
Xiao-Nan
XN
Zhagn
Yu
Y
Wang
Cheng-Ren
CR
Li
Qiao-Ran
QR
Liu
Zong  Xi
Z
Han
Yu-Hao
YH
Shao
Sheng-Wang
SW
Liu
Xian-Gang
XG
Kong
D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D002645:Chickens / Q000821:virology*; D018352:Coronavirus Infections / Q000517:prevention & control / Q000662:veterinary*; D001351:Infectious bronchitis virus / Q000145:classification / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D008562:Membrane Glycoproteins / Q000235:genetics; D010802:Phylogeny; D011201:Poultry Diseases / Q000517:prevention & control*; D064370:Spike Glycoprotein, Coronavirus; D014613:Vaccines, Attenuated / Q000276:immunology; D014759:Viral Envelope Proteins / Q000235:genetics; D014765:Viral Vaccines / Q000276:immunology*
D000914:Antibodies, Viral; D008562:Membrane Glycoproteins; D064370:Spike Glycoprotein, Coronavirus; D014613:Vaccines, Attenuated; D014759:Viral Envelope Proteins; D014765:Viral Vaccines