The blood of mice in each group was collected weekly through the orbital venous post immunization, and then the serums were collected by centrifugation at 3000 rpm for 15 min. The PRV specific glycoproteinB (gB) antibodies were evaluated by the commercial ELISA KIT (Shanghai Hengyuan Bioengineering Co., Shanghai, China) following the manufacturers’ instructions. The results were analyzed with P/N ratios, where P and N denote the OD values of the tested and negative control samples, respectively.