Dataset Information

Age-dependence of hypervirulent fowl adenovirus type 4 pathogenicity in specific-pathogen-free chickens.

ABSTRACT: Hypervirulent fowl adenovirus serotype 4 (hvFAdV-4) has emerged as a major pathogen of hepatitis-hydropericardium syndrome (HHS) with increased mortality in chickens, resulting in economic losses to the Chinese poultry industry since June 2015. Here, we isolated a hypervirulent FAdV-4 (hvFAdV-4) strain (designated GD616) from 25-day-old meat-type chickens with severe HHS in Guangdong Province China in June 2017. The whole genome of the strain GD616 shares high homology with those in the recently-reported hvFAdV-4 isolates in China, with natural deletions of ORF19 and ORF27. A comparative analysis of Hexon and Fiber-2 proteins revealed that 2 unique amino acid residues at positions 378 and 453 of the Fiber-2 protein might be associated with virulence due to their occurrences in all the hvFAdV-4 isolates only. To systemically evaluate the effect of age on the susceptibility of chickens to hvFAdV-4, we used this hvFAdV-4 strain to intramuscularly inoculate 7- to 180-day-old specific-pathogen-free chickens for the evaluation of pathogenicity. These results showed that the pathogenicity of the hvFAdV-4 strain GD616 to chickens exhibited age-relatedness, with younger than 59-day-old chickens showing 100% morbidity and mortality, while 180-day-old chickens still exhibited a hydropericardium syndrome-like clinicopathology with 60% morbidity and 20% mortality. These findings enrich the current available knowledge regarding the pathogenicity of the hypervirulent FAdV-4 virus in chickens with a wide range of ages, which assists with the selection of suitable-aged chickens for the evaluation of hvFAdV-4 vaccines.

SUBMITTER: Yuan F

PROVIDER: S-EPMC8237352 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature

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Age-dependence of hypervirulent fowl adenovirus type 4 pathogenicity in specific-pathogen-free chickens.

Yuan Feng F Song Huiqi H Hou Lei L Wei Li L Zhu Shanshan S Quan Rong R Wang Jing J Wang Dan D Jiang Haijun H Liu Hao H Liu Jue J

Poultry science 20210508 8

Hypervirulent fowl adenovirus serotype 4 (hvFAdV-4) has emerged as a major pathogen of hepatitis-hydropericardium syndrome (HHS) with increased mortality in chickens, resulting in economic losses to the Chinese poultry industry since June 2015. Here, we isolated a hypervirulent FAdV-4 (hvFAdV-4) strain (designated GD616) from 25-day-old meat-type chickens with severe HHS in Guangdong Province China in June 2017. The whole genome of the strain GD616 shares high homology with those in the recently ...[more]

PMID: 34157559

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Dataset Information

Age-dependence of hypervirulent fowl adenovirus type 4 pathogenicity in specific-pathogen-free chickens.

Publications

Age-dependence of hypervirulent fowl adenovirus type 4 pathogenicity in specific-pathogen-free chickens.

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