Longitudinal and Cross-Sectional Evaluation of Two Commercial Swine Breeding Herds to Characterize Neutralizing Antibody Levels following Porcine Epidemic Diarrhea Virus Outbreaks.

Neutralizing antibodies to Porcine Epidemic Diarrhea Virus (PEDV) can be detected by 3 weeks post-infection and remain detectable through at least 24 weeks post-infection. The objective of this study was to evaluate the levels of neutralizing antibodies in sow and piglet serum and sow milk to determine the duration of neutralizing antibodies following PEDV outbreaks. Two farms were selected for the study following outbreaks of PEDV. Monthly, cohorts of sows were sampled and followed through two farrowings. Following each farrowing, samples from piglets and milk were collected. Samples were evaluated for PEDV-neutralizing antibodies by a high-throughput fluorescent neutralization assay. Although neutralizing antibodies to PEDV can be detected throughout 15 months post-outbreak, a decrease in circulating neutralizing antibody levels is noted in farms beginning at six months post-outbreak. With decreasing levels, farms may become more vulnerable to PEDV outbreaks, and practitioners can focus on this time window to implement intervention strategies.

Efficacy of ultraviolet C exposure for inactivating Senecavirus A on experimentally contaminated surfaces commonly found on swine farms.

The objective of this study was to evaluate the efficacy of ultraviolet C light (UVC) for inactivating Senecavirus A (SVA) on three different experimentally contaminated surfaces commonly found in swine farms. An experimental study under controlled conditions assessed the effect of UVC on an SVA isolate on coupons composed of three surface types: cardboard, cloth, and plastic. Each coupon was inoculated with 2 mL of SVA (107.5 TCID50/mL) and 1 mL of PBS or 1 g of feces on the top or bottom surface of the coupon and allowed to dry (90 min at 25℃). Coupons were exposed to UVC in a commercially available pass-through chamber (PTC) for 5 min or in a simulated supply entry room (SER) for 120 min. After exposure, virus isolation was attempted from each coupon and virus titers were determined in cell culture. The efficacy of UVC was determined by the reduction in virus titer for the UVC treated groups compared to their respective non-treated positive controls. UVC was effective at inactivating SVA on plastic surface free of organic material. The plastic coupons inoculated with SVA and PBS had a significantly lower virus titer (>7-log reduction) in both the PTC and SER when compared to their relative positive controls. All other groups in the PTC and SER had a 2-log reduction or less. The reduction in virus titer on the top and bottom inoculated surfaces, following exposure to UVC, were not statistically different. The data from this study provide some guidance when applying UVC for disinfection in the field.

Development and Improvement of an International Webcast Series to Expand the Accessibility of Swine Medicine Resources.

Swine medicine resources and caseloads for teaching and supporting extracurricular training activities vary widely among veterinary colleges and are concentrated in specific regions. Student interest and demand for swine medicine training is broader in geographical distribution. This is illustrated by student membership and attendance at the American Association of Swine Veterinarians (AASV) annual meetings, for example. To explore how concentrated resources might be made more widely available in a cost-effective manner, the Swine Medicine Education Center (SMEC) at Iowa State University's College of Veterinary Medicine looked for ways to leverage existing extracurricular resources with a broader geography of schools and students. This article describes the organization of student chapters of the AASV and the outcomes of a multi-session live audio and video webcast focused on swine medicine topics across North America over a 3-year period. SMEC organized the series with funding provided by the AASV and AASV Foundation. The broadcast series covered a wide range of swine-related topics, including pet pigs, emerging diseases, and regulation of antimicrobials. In its third year, 25 North American and 4 international veterinary schools participated in the series and provided feedback from attendees.

Evaluation of pyramid training as a method to increase diagnostic sampling capacity during an emergency veterinary response to a swine disease outbreak.

OBJECTIVE To develop and evaluate a pyramid training method for teaching techniques for collection of diagnostic samples from swine. DESIGN Experimental trial. SAMPLE 45 veterinary students. PROCEDURES Participants went through a preinstruction assessment to determine their familiarity with the equipment needed and techniques used to collect samples of blood, nasal secretions, feces, and oral fluid from pigs. Participants were then shown a series of videos illustrating the correct equipment and techniques for collecting samples and were provided hands-on pyramid-based instruction wherein a single swine veterinarian trained 2 or 3 participants on each of the techniques and each of those participants, in turn, trained additional participants. Additional assessments were performed after the instruction was completed. RESULTS Following the instruction phase, percentages of participants able to collect adequate samples of blood, nasal secretions, feces, and oral fluid increased, as did scores on a written quiz assessing participants' ability to identify the correct equipment, positioning, and procedures for collection of samples. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that the pyramid training method may be a feasible way to rapidly increase diagnostic sampling capacity during an emergency veterinary response to a swine disease outbreak.