Neutralizing antibody response in serum from experimental groups. Results of the neutralizing assay against the Bas-Rhin CSFV strain for vaccinated, challenged and infected groups. All data are reported as the mean (± SE) of results obtained for the 5 pigs in each group. *p < 0.05 compared each post-challenge value with the respective post-infection value using the Mann–Whitney test. Dotted line with white triangles: CP7_E2alf vaccinated group (CP7 vacc); dotted line with white squares: C-strain vaccinated group (C vacc); full line with black triangles: CP7_E2alf vaccinated and challenged group (CP7 vacc & chal); full line with black squares: C-strain vaccinated and challenged group (C vacc & chal); full line with black circles: infected group.