Efficacy of inactivated variant porcine epidemic diarrhea virus vaccines in growing pigs

Lee, Seung Heon; Yang, Dong-Kun; Kim, Ha-Hyun; Cho, In-Soo

VN titers also increased continuously in all vaccine groups after the first and second vaccinations and were significantly higher than those in the NVC group (p<0.01, unpaired Student's t test) (Fig. 3C) . Although the maximum VN titers in all vaccine groups were detected at 28 dpv, there was no significant difference among the values (p<0.05, Tukey's post hoc test). In contrast, at 14 dpv, the mean VN titer of the ISA201 group (5.0 log2 VN titer) was significantly higher than those of the IMS1313 (3.25 log2 VN titer) and IMS gel (3.5 log2 VN titer) groups. The ISA206 group also exhibited a higher mean VN titer (5.5 log2 VN titer) than those of the IMS1313 and IMSgel groups, while the mean VN titers of the ISA206 and ISA201 groups were comparable (p<0.05, Tukey's post hoc test) (Fig. 3D ). These findings indicated that the ISA201 and ISA206 adjuvants induce a virus-neutralizing antibody response more Fig. 2 . Clinical score and viral shedding in pigs after challenge with virulent homologous virus (porcine epidemic diarrhea virus [PEDV] QIAP1401-p11). Diarrhea severity was scored (A), and viral shedding in feces was monitored by real-time reverse transcription polymerase chain reaction (B). The letter "a" above the bars indicates a significant difference among the experimental groups (p < 0.05, Fisher exact test), whereas "b" indicates no significant difference. NVC, non-vaccinated control. rapidly than do the IMS1313 and IMSgel adjuvants.