Data limitations challenge PEDv research
Feb. 3, 2015
by Erica Shaffer
DES MOINES – New research found an extremely small risk of transmitting porcine epidemic diarrhea virus (PEDv) through feed or ingredients derived from swine. But the small amount of data available for the project posed a challenge to researchers.
The Checkoff commissioned the study, "Risk assessment of feed ingredients of porcine origin as vehicles for transmission of Porcine Epidemic Diarrhea Virus (PEDV)". Researchers at the Univ. of Minnesota coordinated the project.
The assessment included rendered ingredients, ingredients derived through spray-drying porcine swine blood and ingredients from hydrolyzed porcine tissues. Researchers used data acquired from a variety of sources, including industry, scientific literature, experimental studies and industry reports. But the dearth of specific data constrained the project, the researchers said in their report.
"It is noted that most of the data used in the analysis were unavailable at the commencement of the project, and are derived from very recent studies that have yet to be independently replicated," the researchers wrote.
Among the project findings:
• The risk of PEDv surviving the processes of rendering and hydrolysis (peptone production) are negligible.
• The possibility of virus survival is inherently greater in spray-drying porcine blood if non-thermal mechanisms are ignored. But, overall, currently available data indicate an extremely small probability of PEDv surviving the spray-drying process and current commercial storage periods.
Researchers noted that information on inactivation of PEDV by spray drying became available during the project, while data on PEDv contamination of raw materials were unavailable for rendering and hydrolyzed protein sources. Additionally, researchers used experimental data on the thermal inactivation of PEDv because previously published studies "did not enable adequate portrayal of the thermal inactivation kinetics of PEDv".
The risk assessment findings could change as new information becomes available, the researchers added. The full report is available on the Pork Checkoff website.