Attenuation and Immunogenicity of a Live High Pathogenic PRRSV Vaccine Candidate with a 32-Amino Acid Deletion in the nsp2 Protein

Figure 4

Virus neutralizing titers. Serum collected at −7, 0, 7, and 14 days after challenge were examined for neutralization with PRRSV. The data were expressed as the geometric mean ± S.D. of 5 pigs in each group. The serum was considered neutralizing at fourfold or higher dilution in positive response.