Porcine epidemic diarrhea virus suddenly and profoundly affected the United States swine industry in its emergence in May 2013.1 Although the direct route of transmission is fecal-oral transmission, little is known about other possible routes of transmission and risk factors for spread among swine populations, including the role of transport vehicles and aerosolized virus.2–4 Recently, several PEDV outbreaks were suspected to be associated with the consumption of PEDV-containing feed or feed ingredients.5 Since those outbreaks were reported, it has been confirmed that feed is a potential vehicle for PEDV transmission, and this has prompted investigations into reducing infectivity risk attributable to contaminated diets or feed ingredients.6–9 Additionally, PEDV is highly transmissible in the United States; however, little is known about the overall magnitude of transmissible risk that PEDV-infected feed constitutes. Furthermore, the authors are aware of no data that define the minimum infectious dose of PEDV detected in feed. Therefore, the objective of the study reported here was to determine the infectious dose of PEDV in feed by use of a 10-day-old pig bioassay.
Supported in part by the National Pork Board (Grant No. 14-159).
Presented in abstract form at the 2015 American Society of Animal Science Midwest Section Annual Meeting, Des Moines, Iowa, March 2015.
Porcine epidemic diarrhea virus
Real-time quantitative PCR
Excede, Zoetis, Florham Park, NJ.
ATCC CCL-81, American Type Culture Collection, Rockville, Md.
High Phos 2700 GT, DSM Nutritional Products, Parsippany, NJ.
Stainless steel meat mixer, Cabela's Inc, Sidney, Neb.
All Natural Starter 2, Heartland Co-Op, Alleman, Iowa.
Fatal-Plus, Vortech Pharmaceuticals Ltd, Dearborn, Mich.
MagMAX pathogen RNA/DNA kit, Thermo Fisher Scientific, Waltham, Mass.
Kingfisher-96, Thermo Fisher Scientific, Waltham, Mass.
Path-ID Multiplex One-Step RT-PCR kit, Thermo Fisher Scientific, Waltham Mass.
Nikon Eclipse TI-U microscope, Nikon Instruments Inc, Melville, NY.
SAS, version 9.3, SAS Institute Inc, Cary, NC.
Cochrane RA, Woodworth JW, Dritz SS, et al. Evaluating chemical mitigation of porcine epidemic diarrhea virus in swine feed and ingredients (abstr), in Proceedings. Am Soc Anim Sci Midwest Sect Am Dairy Sci Assoc Midwest Branch Joint Meet 2015;41–42.
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Composition of feed inoculated with PEDV and used for challenge exposure of 10-day-old pigs.
|Choice white grease||1.00|
|Calcium phosphate (monocalcium)||1.40|
|Trace mineral premix†||0.15|
|Additional additive premix‡||0.50|
Contained 46.5% crude protein.
Each kilogram contained 26.4 g of Mn, 110 g of Fe, 110 g of Zn, 11 g of Cu, 198 mg of I, and 198 mg of Se.
Each kilogram contained 4,409 U of vitamin E, 44 mg of biotin, 992 mg of pyridoxine, 331 mg of folic acid, and 110,229 mg of choline.
Each kilogram contained 4,400,000 U of vitamin A, 551,146 U of vitamin D3, 17,637 U of vitamin E, 1,764 mg of menadione, 3,300 mg of riboflavin, 11,023 mg of pantothenic acid, 19,841 mg of niacin, and 15 mg of vitamin B12.