Basic Study
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Virol. Feb 12, 2016; 5(1): 23-30
Published online Feb 12, 2016. doi: 10.5501/wjv.v5.i1.23
Pathogenicity of a currently circulating Chinese variant pseudorabies virus in pigs
Qing-Yuan Yang, Zhe Sun, Fei-Fei Tan, Ling-Hua Guo, Yu-Zhou Wang, Juan Wang, Zhi-Yan Wang, Li-Lin Wang, Xiang-Dong Li, Yan Xiao, Ke-Gong Tian
Qing-Yuan Yang, Zhe Sun, Fei-Fei Tan, Ling-Hua Guo, Yu-Zhou Wang, Juan Wang, Zhi-Yan Wang, Li-Lin Wang, Xiang-Dong Li, Yan Xiao, Ke-Gong Tian, National Research Center for Veterinary Medicine, Luoyang 471003, Henan Province, China
Ke-Gong Tian, College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou 450002, Henan Province, China
Author contributions: Yang QY, Sun Z, Tan FF, Guo LH, Wang YZ, Wang J, Wang ZY and Wang LL performed the experiments; Li XD performed the statistical analysis and wrote the paper; Li XD and Tian KG analyzed the data; Tian KG and Xiao Y conceived and designed the experiments; all authors read and approved the final manuscript.
Supported by Major Science and Technology Program in Henan Province, No. 131100110200.
Institutional review board statement: All procedures involving animals were reviewed and approved by the Institutional Animal Care and Use Committee of the National Research Center for Veterinary Medicine (IACUC protocol number: 2015010402). Conventional animal welfare regulations and standards were taken into account.
Institutional animal care and use committee statement: All procedures involving animals were reviewed and approved by the Institutional Animal Care and Use Committee of the National Research Center for Veterinary Medicine (IACUC protocol number: 2015010402).
Conflict-of-interest statement: The authors declare no conflict of interest.
Data sharing statement: Technical appendix, statistical code, and dataset are available from the corresponding author at tiankg@263.net.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Dr. Ke-Gong Tian, National Research Center for Veterinary Medicine, Cuiwei Road, High-Tech District, Luoyang 471003, Henan Province, China. tiankg@263.net
Telephone: +86-379-60687971 Fax: +86-379-60687976
Received: May 8, 2015
Peer-review started: May 9, 2015
First decision: June 18, 2015
Revised: November 17, 2015
Accepted: December 1, 2015
Article in press: December 2, 2015
Published online: February 12, 2016
Processing time: 269 Days and 3.7 Hours
Abstract

AIM: To test the pathogenicity of pseudorabies virus (PRV) variant HN1201 and compare its pathogenicity with a classical PRV Fa strain.

METHODS: The pathogenicity of the newly-emerging PRV variant HN1201 was evaluated by different inoculating routes, virus loads, and ages of pigs. The classical PRV Fa strain was then used to compare with HN1201 to determine pathogenicity. Clinical symptoms after virus infection were recorded daily and average daily body weight was used to measure the growth performance of pigs. At necropsy, gross pathology and histopathology were used to evaluate the severity of tissue damage caused by virus infection.

RESULTS: The results showed that the efficient infection method of RPV HN1201 was via intranasal inoculation at 107 TCID50, and that the virus has high pathogenicity to 35- to 127-d old pigs. Compared with Fa strain, pigs infected with HN1201 showed more severe clinical symptoms and pathological lesions. Immunochemistry results revealed HN1201 had more abundant antigen distribution in extensive organs.

CONCLUSION: All of the above results suggest that PRV variant HN1201 was more pathogenic to pigs than the classical Fa strain.

Keywords: Pseudorabies virus; Pathogenicity; Virus variant; Gross pathology; Histopathology

Core tip: Pseudorabies virus (PRV) variant HN1201 has pathogenicity in 35 to 127-d old pigs via intranasal inoculation at 107 TCID50. Intranasal inoculation is more efficient than intramuscular inoculation for PRV challenge. PRV variant HN1201 showed higher pathogenic ability, as shown by the more severe clinical symptoms, pathological lesions, and abundant antigen distribution in extensive organs than the classical PRV Fa strain.