The objective of this research was to evaluate the potential transmission of porcine epidemic diarrhea virus (PEDV) to neonatal pigs from PEDV-contaminated feed components. Feed components retained at manufacturing facilities shortly after the emergence of PEDV in the United States were collected and submitted to the Iowa State University Veterinary Diagnostic Laboratory and tested positive for PEDV by polymerase chain reaction (PCR). A feed suspension was subsequently fed to PRRSV- and PEDV-negative neonatal pigs for 7 consecutive days during which time the pigs were monitored for development of clinical signs that included vomiting and/or diarrhea. Rectal swabs were collected daily to evaluate PEDV shedding in feces. None of the pigs fed the feed components submitted by manufacturers developed diarrhea and PEDV was not detected from rectal swabs collected from challenged piglets. However, piglets administered complete feed spiked with PEDV which was isolated in the laboratory (positive control pigs) developed diarrhea and shed PEDV as detected by PCR testing. Additionally, the positive control pigs were the only group that exhibited microscopic evidence of viral enteritis. Although the PEDV-contaminated feed components retained by manufacturers did not cause clinical disease or induce shedding of PEDV under the conditions of this study, the clinical findings and laboratory testing of the positive control pigs confirmed that feed spiked with a live PEDV cell-culture isolate can serve as a vehicle for transmission of virus leading to the development of clinical disease in neonatal piglets.

Contact information:
Angela E. Pillatzki
Animal Disease Research and Diagnostic Laboratory
South Dakota State University
Box 2175, North Campus Dr.
Brookings, SD 57007
[email protected]

Phil Gauger
Veterinary Diagnostic Laboratory
Iowa State University
1600 South 16th St.
Ames, IA 50011
[email protected]