Additional discriminatory peaks found in the current study were very similar (MW differences ≤0.3 kDa) to those identified in other PRRS-related proteomic studies (Table 3) . They corresponded to the following proteins: Glyceraldehyde-3-phosphate dehydrogenase, Proteasome activator hPA28 subunit beta, S100 calcium binding protein A10, Galectin 1, and Gastric-associated differentially expressed protein YA61P [26] ; Heat shock 27 kDa protein 1, Superoxide dismutase 2, Myoglobin, and Vacuolar protein sorting 29 [29] ; Heat shock protein 27 kDa and Nucleoside diphosphate kinase A [30] ; Heat shock 27 kDa protein 1, Galectin 1, and Ubiquitin [31] .