Amy Millmier Schmidt
Date of this Version
Boyles, E. 2018. Surveillance and evaluation of manure treatment practices for mitigation of the porcine epidemic diarrhea virus (PEDv) in commercial swine farm settings. Thesis. University of Nebraska - Lincoln. December 2018.
The emergence of the porcine epidemic diarrhea virus (PEDv) in the United States in 2013 resulted in billions of dollars in annual losses for the U.S. swine industry. Infection with PEDv causes severe diarrhea and vomiting in pigs, spreads rapidly through ingestion of infected manure, and produces nearly 100% mortality in pre-weaned piglets. Because swine manure slurry is a valuable crop nutrient source, concerns about virus persistence in stored manure remain a major barrier to proper manure management. Proper manure handling and application practices are necessary to control the risk of pathogen re-infection at affected production sites or infecting new sites through virus-contaminated manure handling equipment. alkaline stabilization managed to control potential infection from manure sources. Alkaline stabilization of manure with hydrated lime to pH 10 for at least one hour was proven an effective treatment to render PEDV-positive swine manure slurry non-infective as confirmed via live pig bioassays. This treatment goal can be achieved with a dosing rate of 22.7 kg (50 lbs) of quicklime per 3,785 L (1,000 gal) of swine manure. Ammonia loss from simulated storage pit and manure tanker settings were approximately 30% and 15%, respectively, representing a potential loss in nutrient value from volatilized ammonia nitrogen. To minimize the potential for any disease outbreak, strict biosecurity planning and implementation of biosecure practices is essential. A field study was conducted to assess the effectiveness of industry recommended biosecurity practices to eliminate PEDv at critical control points (CCPs) on three commercial swine farms in the midwestern U.S. following disease outbreaks. Sampling of CCPs on each farm was conducted immediately following confirmation of PEDv on the farms, immediately following disinfection and at 6, 12 and 18 months post-disinfection. We conclude, based on survey results, that practices used to control PEDv in commercial swine farm settings are effective at eliminating the virus and preventing reinfection of the herd with the same viral strain.
Advisor: Amy Millmier Schmidt