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

A 25.0 g sample of each feed matrix was collected and placed in its appropriate bottle (250 mL Nalgene, square wide-mouth high-density polyethylene; Thermo Fisher Scientific, Waltham, MA) and received no virus acting as the negative control. For the feed treatment batches, a benchtop paddle mixer was used as previously described (Schumacher et al., 2016) for mixing feed additives with FEED. Mixing time was 3.0 min, which was previously verified as adequate to achieve a CV of <10% as described by McCoy (2005) , using a chloride mixer efficiency procedure (QuanTab; Hach Co., Loveland, CO). A V-mixer (Cross Flow Blender; Patterson-Kelley Co., East Stroudsburg, PA) was used to mix feed additives with SDPP. A mixer efficiency test was performed using spray-dried bovine plasma and resulted in a uniform mix according to manufacturer's recommendation with a mix time of 7.0 min (MicroTracer-F; Micro-tracers Inc., San Francisco, CA).