Abstract: The immunogenic peptides of five pseudoraibes virus (PrV) isolates were determined and compared using murine as well as swine sera. Western blotting technique was employed to visualize the immunogenic peptides. Marked differences in the number and kinds of immunogenic peptides among the viruses were observed using either the murine or swine sera. 12 and 13 immunogenic peptides were detected using murine and swine sera respectively. Murine serum was noted to detect peptides of higher molecular weights as compared to those detected by swine serum. The protein of 76.00 Kda was detected when both sera were used although minor variations in the molecular weights were noted for the peptides detected by both kinds of sera. The results obtained indicated that the recognition of different protein peptides of the virus by immune system is an animal species dependent.