Tk-deleted pseudorabies virus retains high pathogenicity in rats

• Published in: Journal of veterinary research 2021-12, Vol.65 (4), p.401-405
• Main Authors: Zhang, Lirong, Ruan, Keyue, Sang, Guoju, Xu, Zhaoyang, Tong, Wu, Yu, Hai, Shan, Tongling, Gao, Fei, Li, Liwei, Kong, Ning, Tong, Guangzhi, Zheng, Hao
• Format: Article
• Language: English
• Subjects: Ganglia; Inoculation; Kinases; Lethal dose; Pathogenicity; Pseudorabies; pseudorabies virus; rat; Review; Rodents; Spinal cord; Thymidine; Thymidine kinase; Trigeminal ganglion; Virulence
• ISSN: 2450-7393; 2450-8608; 2450-8608
• DOI: 10.2478/jvetres-2021-0056

The pseudorabies virus (PRV) gene encoding thymidine kinase (tk) is an important virulence-associated factor. Attenuation of PRV in susceptible animals is a frequent result of tk deletion. The aim of the study was to assess the pathogenicity of tk-deleted PRV in rats. Sprague Dawley rats were infected with the tk-deleted PRV strain SuHV-1 ΔTK:247 intranasal or intramuscular inoculation. PRV loads in ten tissues from dead and euthanised rats were determined using real-time PCR. Infection with SuHV-1 ΔTK:247 could cause death in rats. The 50% lethal dose (LD ) of SuHV-1 ΔTK:247 intranasal inoculation was 10 TCID in rats. Intramuscular inoculation required a higher dose of SuHV-1 ΔTK:247 (10 TCID ). A high SuHV-1 ΔTK:247 titre was observed in the trigeminal ganglia or spinal cord of dead rats. The results of this study show that rats are highly susceptible to PRV infection, and tk deletion did not completely diminish the pathogenicity of PRV in rats.