Figure 2.

Neutralizing antibody titres in the serum and milk collected from the pregnant sows after prime‐boost immunizations. (a) Serum was collected from the pregnant sows of all groups on day 35 post first immunization and (b) milk was collected on day 1 postfarrowing and their neutralizing antibody titres were analysed. Neutralizing antibody titres were expressed as dilutability at 50% inhibition of PEDV infection in Vero cells. Data are represented as mean ± SD, n = 5. ** stand for P < 0·01 and * stand for P < 0·05. Groups: (○) DMEM + DMEM; (△) PEDV + PEDV; (□) coated PEDV‐loaded microspheres + coated PEDV‐loaded microspheres; (●) PEDV + inactivated PEDV vaccines; (▲) coated PEDV‐loaded microspheres + inactivated PEDV vaccines; (■) inactivated PEDV vaccines + inactivated PEDV vaccines