Determining the impact of commercial feed additives as potential porcine epidemic diarrhea virus mitigation strategies as determined by polymerase chain reaction analysis and bioassay()

Gebhardt, Jordan T; Woodworth, Jason C; Jones, Cassandra K; Tokach, Mike D; Gauger, Philip C; Main, Rodger G; Zhang, Jianqiang; Chen, Qi; DeRouchey, Joel M; Goodband, Robert D; Stark, Charles R; Bergstrom, Jon R; Bai, Jianfa; Dritz, Steve S

No PEDV RNA was detected in fecal swabs before initiation of the bioassay, and negative control pigs remained negative for PEDV genetic material for the full length of the bioassay as assessed by fecal swabs and cecal content collected at necropsy (Table 4 ). Genetic material was detected in fecal swabs for all three pigs in the d 0 untreated FEED and SDPP bioassay rooms beginning at 2 dpi, and viral shedding was observed for the duration of the bioassay. No d 1 untreated FEED pigs had detectible RNA in fecal swabs or cecal contents throughout the bioassay. All three d 3 post-laboratory inoculation untreated SDPP pigs began shedding virus at 2 dpi, whereas the d 3 post-laboratory inoculation untreated FEED pigs had no detectible RNA in fecal swabs throughout the bioassay or cecal content at necropsy. No d 21 post-laboratory inoculation untreated FEED or SDPP pigs had detectible virus in fecal swabs or cecal contents. Thus, pigs became infected with PEDV with both FEED and SDPP at d 0 post-laboratory inoculation as well as d 3 post-laboratory inoculation in SDPP.