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PRRS: Obtain Current

When a swine disease strikes, you want helpful information immediately. Fortunately, there’s SOURCE, a systematic approach to disease control, prevention and management using a step-by-step process developed by Boehringer Ingelheim.

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

Know the symptoms of PRRS

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-Pigs 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

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 PCR testing for PRRS, as well as provide a variety of other services. Talk to your veterinarian for advice on sampling.