Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) is a virus that causes potentially severe disease in swine with significant economic consequences for producers. There are two major strains of PRRSV, one primarily found in North America (U.S. strain), and one primarily prevalent in Europe (E.U. strain). Although they are genetically quite distinct, infection with both strains exhibits very similar clinical signs, which include respiratory, pneumonia-like symptoms and reproductive complications in sows.
The industry is primarily effected by the reproductive issues that are caused by the virus. Late-term abortion, stillbirths, mummifications, and foetal deaths during pregnancy occur with 35-50% of piglets. Piglets born alive are generally weak and the mortality of live-born piglets is 50-100% in most litters. Sows infected with PRRSV show a slow return to service. This on average, costs the swine industry $644 million annually, mostly due to loss of litters.
It is, therefore, an industry standard to test animals prior to shipping and to test boars prior using their semen. Additionally, routine surveillance of production sites is part of health and wellness management. The VDX offers same-day turnaround time to facilitate timely shipping and transport of live animals, and use of boar semen the same-day to maintain optimal semen quality and fertility.
There are two testing methods available for PRRSV.
Detection of the PRRS virus: Polymerase Chain Reaction (PCR) is an extremely accurate, sensitive, and fast method to detect the presence of the PRRS virus in a wide variety of sample types. Potential sample types include serum, ear stick, oral fluid, raw semen, and environmental samples.
The utilisation of an internal PCR control target in every reaction ensures that no PCR inhibition has taken place and negative results can be reported with confidence. In addition to the qualitative test that determines whether a virus is present, the VDX also offers a quantitative PCR test that will accurately estimate the number of PRRS virus particles in the sample. The qualitative test carries the same-day turnaround time.
PRRSV antibody detection: Enzyme-linked immunosorbent assay (ELISA) is a very specific and sensitive assay for detecting PRRSV antibodies in serum. Presence of PRRSV antibodies indicates that the animal had been previously exposed to the PRRS virus. The test is often used in conjunction with the PCR test. The use of two different tests provides maximum confidence in negative test results. The ELISA test carries a next-day turnaround.
Acceptable sample types:
- Serum (red top or red-grey top tubes, or capillary tubes; can be pooled by up to five samples)
- Ear sticks (swabs in saline solution; can be pooled by up to five samples)
- Oral fluids (collected from cotton ropes hung in the pen, tested individually)
- Raw semen (can be pooled by up to three samples)
- Environmental samples (preferably collected on scent-free Swiffer pads)
If sending through courier service, please send with an ice pack to maintain sample quality.
Samples for PCR testing for PRRS must be received by 2:00 pm for same-day turnaround. ELISA samples are tested the next day. If same-day testing is required, please inform the lab prior to the day of arrival, so arrangements can be made accordingly.