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
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.
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.