So far, 2015 has proven to be a fairly mild year for PEDv infection compared to the devastation that hit in 2014. Nonetheless, it is a concerning virus for pork producers and continued focus for Pipestone Applied Research (PAR). In 2014, PAR proved that contaminated feed could serve as a vehicle for PEDv transmission and also proved intervention to help reduce the spread through feed through SalCURB utilization.
Pipestone’s most recent research publishing took another fresh take on PEDv survivability, this time looking at individual ingredients. “Every producer is out there wondering what else they can do to minimize the risk of PEDv infection.” stated Dr. Scott Dee, Director of Research at Pipestone. “Our research is aimed at helping producers safeguard the health of their animals and business.”
The research study’s objectives were to identify feed ingredients that promote or inhibit PEDv survivability, and measure the affect of SalCURB on those same ingredients. Common feed ingredients tested can be seen on the right, and included corn, soybean meal, DDGS, porcine by-products, vitamins, fats, and amino acids.
The container model was uniquely designed to prevent crossover contamination and started with PEDv negative status – replicating the process of ingredients coming “clean” from processing plants that would be contaminated after shipping. Post controlled contamination, the samples were tested at day 1, 7, 14, and 30 post inoculation in conjunction with South Dakota State University. PCR positive samples were then tested by cell culture (seeing if the virus was live). What samples could not grow via cell culture were tested in a bio-assay (fed to pigs to see if they would get sick) The results were both surprising and alarming.
Pipestone learned that approximately 50% of the tested ingredients could harbor live virus for extended periods of time. Two clusters of ingredients are shown: those that supported virus (circled in green), and those where no live virus was detected even on day 1 post inoculation (circled in red). Soybean meal proved to be the most conducive environment for PEDv; proving positive 180 days post inoculation. The amount of virus still living was easily enough to still infect pigs.
Complete feed was able to provide positive testing out to 45 days while bi-products and synthetic amino acids were only studied out to 30 days. Interestingly, meat and bone meal, red blood cells, and DDGs still had live virus during this timeframe. This is an important takeaway that these ingredients can support live viruses in cold weather with so many producers storing these ingredients, especially DDGs outdoors.
Just as surprising as the ingredients that did support live virus was the ingredients that did not. Porcine plasma, corn, and other synthetic plasmas that were thought to be the worse-case scenario for virus survivability early on proved to be less risky. In all cases, ingredients treated with SalCURB, where unable to sustain live virus, including soybean meal.
With such a large array of ingredients supporting virus, it is no doubt hard to manage and further stresses the need for heightened mill and ingredient biosecurity. The Pipestone team is working hard to determine the best way to manage these newly discovered risk factors. For questions on Pipestone’s study, please contact Robin Gilbertson at firstname.lastname@example.org or 507.825.4211.