60 Use of environmental monitoring to inform biosecurity compliance in a swine health challenge

Abstract

Abstract As endemic and foreign diseases threaten the U.S. swine herd, producers are scrutinizing on-farm biosecurity practices. Environmental monitoring may help inform biosecurity compliance. Unfortunately, the Kansas State Swine Teaching and Research Center suffered an outbreak of porcine epidemic diarrhea virus (PEDV) in March 2019. The objective of this research was to use environmental monitoring to evaluate biosecurity risk on a farm experiencing a viral outbreak. In a completely randomized design, environmental swabs were collected after barn sanitation on 14, 28, and 42-days after initial PEDV diagnosis from four zones: 1) pig contact surfaces within barns, 2) non-pig contact surfaces within barns, 3) outside barns and inside offices, and 4) transition areas. Swabs were analyzed for PEDV, rotavirus, and Enterobacteriaceae at a veterinary diagnostic laboratory. Data were analyzed using the GLIMMIX procedures of SAS, v 9.4 (Cary, NC). There was a significant time × zone interaction for PEDV (P < 0.0001), where swabs from non-pig contact areas within barns on d 28 (Zone 2) had greater (P < 0.05) levels of PEDV than pig-contact areas (Zone 1) on d 14, 28, or 42. No other interactions existed, and they were therefore removed from the statistical model. Time did not affect (P > 0.05) any measured response criteria. No PEDV was detected (45.0 Ct) from Zone 1 due to recent sanitation, but viral presence was highest (P < 0.05) in non-pig contact areas inside barns and was tracked outside of barns and through transition zones (32.9, 34.3, and 38.5 Ct for zones 2, 3, and 4, respectively). There was no detected difference (P > 0.05) for rotavirus or Enterobacteriaceae in time or zone. In conclusion, producers experiencing a PEDV outbreak may successfully decontaminate pig-contact surfaces, but still have risk throughout the farm. Biosecurity practices should support preventing cross-contamination from other contaminated areas.