Current projects

Postmortem sampling as a convenient, welfare-friendly and efficient PRRS monitoring tool: A pilot project

Optimizing PRRSv detection in breeding herds undergoing virus elimination is key. Developing a postmortem sampling methodology that is not only practical and saves time but also contributes to increasing PRRSv diagnostic sensitivity will significantly improve PRRSv status classification of herds. This pilot study with two specific aims: 1) determine whether postmortem sampling of suckling piglets allows for the detection of PRRSv in farms undegoing elimination and, 2) to determine which of the postmortem specimens has the highest PRRSv sensitivity. Additionally, since the sampling is collected on dead pigs, the sampling methodology is entirely humane and improves animal welfare since invasive sampling and pig restraint are eliminated.

This project is sponsored by the Hatch Capacity Grant.

Porcine epidemic diarrhea virus (PEDV) time‐to‐stability and associated factors in the United States breeding herds

Porcine epidemic diarrhea virus (PEDV) was first identified in the United States (U.S.) in April 2013. The epidemic period lasted for approximately 1.5 years, transitioning to endemic levels in 2015. Since then, little work has been published on how long it takes a sow herd to achieve a stable status (i.e., time-to-stability or TTS).

The objective of this study is to estimate the PEDV TTS in the U.S. breeding herds during the epidemic and endemic periods and assess associated factors.

This project is sponsored by SHIC.

Monitoring PRRSV2 variants of interest in the U.S.

Leveraging the data sharing agreements between MSHMP participants, MSHMP, and main Veterinary Diagnostic Laboratories in the U.S., a comprehensive PRRSV dataset comprising ORF5 sequences from breeding and growing pig is used to monitor and describe and the occurrence of PRRSV2 variants of interest. We investigate cases occurrence in space and time, as well as production impact, time to stability, and factors associated with variant's occurrence. Some examples of variants of interest monitored are the 1C.5 (formerly referred to as L1C 144 variant), 1C.2 (associated mainly with RFLP pattern 1-2-4), and 1H.18 (associated mainly with RFLP patterns 1-12-2 and 1-8-4).

This project is sponsored by SHIC.

Monitoring the detection of PRRSV variant 1H.18

Updates on monitored PRRSV variants

Updates on monitored PRRSV variants (May 16, 2025)

Assessment of farm surface PRRSV contamination through viability RT-qPCR

Farm biosecurity measures and the level of compliance play a crucial role, especially in an industry where one individual oversees large populations of growing pigs across different sites. Growing pig caretakers move between sites to conduct daily chores such as ensuring barns are well-ventilated and pigs have proper access to feed and water. As most growing pig sites lack shower-in/shower-out facilities, there is a probability of fomite contamination and virus dissemination across sites of different PRRSV statuses. Understanding whether frequently touched surfaces by personnel contain viable PRRSV is crucial for raising awareness of the transmission risk and encouraging the industry to reconsider and enforce biocontainment procedures. We conducted a surface contamination assessment sampling project in PRRSV-positive growing pig farms using a novel viability quantitative RT-qPCR (v-RT-qPCR) assay, to determine whether viable PRRSV can be detected on frequently touched surfaces by farm personnel.

This project is funded by the American Association of Swine Veterinarians (AASV)

Use of post-mortem samples from growing pigs to detect common swine pathogens

Most post-weaning sampling relies on oral fluid samples since jugular venipuncture can be time-consuming and requires skilled personnel. Assessing whether easy to collect post-mortem samples (i.e., tongue tip fluid [TTF], intracardiac blood [IC], oral/nasal swabs [ONS], rectal swabs [RS], superficial inguinal lymph nodes [SILN]) can provide value for diagnosis and monitoring in the post-weaning stages is necessary as this methodology can be adopted by the industry when resources are scarce, even though they are not the gold standard specimen. Therefore, the objectives of this study are 1) to assess the sensitivity and specificity of TTF, ONS, and SILN in growing pigs when compared to IC, in the presence of porcine reproductive and respiratory virus (PRRSV); and, 2) to describe the detection of Porcine Circovirus type 2 and 3 (PCV-2, PCV-3), Porcine Parvovirus type 1 and 2 (PPV-1, PPV-2), Lawsonia intracellularis (Li), and Influenza A virus (IAV), through RT-PCR of collected post-mortem samples (e.g., TTF, ONS, RS, SILN).

This project is funded by the Swine Health Information Center (SHIC)