Whatever your stated goals, it’s important to understand where PRRS has or has not been present in your herd. The testing of blood, oral fluids and the environment may be essential in obtaining your current status.


    Recognizing clinical signs of PRRS is important to spotting the disease early. Work with your herd veterinarian to further diagnose if any of these symptoms are present:

    Breeding-Herd Symptoms

    • Late-term abortions
    • Premature farrowing
    • Delivery of stillborn, weak/listless/non-viable or mummified piglets
    • Anorexia and fever
    • Sow mortality

    Growing-Pig Symptoms

    • Fever, depression, reduced appetite
    • Discharge from eyes and nose
    • Respiratory symptoms; specifically, labored abdominal breathing often referred to as “thumping”
    • Uneven growth, gaunt appearance
    • Increased culls and mortality post-weaning
  • Testing

    Which test is right for you?

    PRRS infection is widespread in U.S. herds, so care must be taken to both confirm an active infection and to rule out other infectious diseases. Any tentative clinical diagnosis should be confirmed by detection of the PRRS virus. The most common diagnostic tests used for confirming PRRS include:

    • Polymerase chain reaction (PCR) – Detects presence of virus
    • ELISA – Detects presence of antibody following infection
    • Gene sequencing – Differentiates PRRS virus strains

    The primary sample types that can be collected and used for diagnostic testing include:

    • Blood/Serum
    • Oral fluids
    • Tissues (lung, tonsil and/or lymph node)
    • Environmental samples

    Sample Diagnostic Testing for Replacement Gilts:

    Entry into Gilt Pool Exiting Gilt Pool/Prior to
    Breeding-Herd Entry
    Blood/Serum – PCR and ELISA Blood/Serum – PCR and ELISA
    Oral – PCR Oral – PCR

    Sample Diagnostic Testing for Sows:

    Routine Monitoring/Testing Due-to-Wean Piglets
    Blood/Serum – PCR

    Testing Growing Pigs for PRRS

    8–10 Weeks of Age
    (15–20 pigs)
    12–14 Weeks of Age
    (15–20 pigs)
    18–20 Weeks of Age
    (15–20 pigs)
    Blood/Serum – PCR and ELISA Blood/Serum – PCR and ELISA Blood/Serum – PCR and ELISA
    Oral – PCR Oral – PCR Oral – PCR

    Tissue samples can be used to further confirm disease. Always work with your veterinarian when developing a diagnostic testing program and collecting samples.

  • Tips for Best Sample Collection

    Detection of PRRS virus is best performed in affected pigs during the early stages of PRRS infection:

    • Weak-born, lethargic newborn/neonatal pigs
    • Weak, off-feed and feverish post-weaned pigs
    • Sows/Gilts exhibiting clinical signs, recently aborted, feverish and/or off-feed

    Good choices for diagnostic samples and tissues for virus detection methods include:

    • Blood/Serum
    • Oral fluids
    • Lung, lymph node, tonsil and/or spleen tissues

    Other tips:

    • Collect samples and immediately refrigerate/place on ice.
    • Both fresh and formalin-fixed tissue samples, if possible
    • Send samples overnight to a laboratory using an insulated box with ice packs.
    • Completely fill out laboratory submission form.

    HMC Diagnostics Lab
    Boehringer Ingelheim Vetmedica, Inc.’s Health Management Center (HMC) is one of the leading swine-specific diagnostic laboratories in North America. HMC can conduct ELISA and PCR testing for PRRS, as well as provide a variety of other services. Talk to your veterinarian for advice on sampling.