Science Page: Comparison of individual oral fluids, pooled oral fluids and Swiffer™ environmental samples of drinkers for the detection of influenza A virus and PRRS virus by PCR

This is our Friday rubric: every week a new Science Page from the Bob Morrison’s Swine Health Monitoring Project. The previous editions of the science page are available on our website.

This week,  we are sharing a study done by Taylor Homann, a DVM student at the University of Minnesota in collaboration with the Swine Vet Center and Boehringer Ingelheim, regarding the comparison of several sample types to detect PRRS and flu by PCR.

Key points:

  • Pooling oral fluid samples seems to be a good strategy to determine the status of a farm (positive/negative) for influenza A virus (IAV) and PRRSV.
  • Sampling water cups using environmental Swiffer™ samples appears to be a sensitive approach to detect IAV at the pen level.
  • However, sample size has been limited to one farm.

Objective:

The objective of this project was to compare the sensitivity of pooled pen oral fluids (OF) and environmental samples (Swiffer™ kits on water cups) using individual pen oral fluids as the standard.

Methods:

Fifteen paired environmental and individual pen OF were collected at days 3, 7, 10, 17, 24 and 31 post placement in two different nursery farms. Environmental samples (ES) were taken using Swiffer™ cloths to sample the bottom of water cups (both pans and bowls), focusing around nipples. After individual samples were collected, pen OF were pooled by 3.

Results:

There was an overall sensitivity of 71% (IAV) and 14% (PRRS) for the ES samples compared to individual OF. Pooled oral fluids samples had an overall sensitivity of 50%(IAV)and 80%(PRRSV)relative to individual pen OF.

Homann PRRS flu Oral fluid water cup sample comparison

In summary, ES appears to be a good strategy when sampling for IAV and not a reliable option when trying to diagnose PRRSV.

Attending IPVS in China? Support Minneapolis 2022!

IPVS_2022.002Help us bring the IPVS back to the United States by supporting “Minneapolis 2022.” The last time the IPVS was held in the US was 2002, and before that, 1976. It’s time to bring it back!

We are thrilled to present the “Minneapolis 2022” bid at IPVS in China in June and working together with producers, veterinarians, academia and allied industry to make “Minneapolis 2022” the best IPVS ever! If you are attending IPVS China, please spread the word, join us at the booth and, of course, vote for “Minneapolis 2022” at the general meeting.

For more information: z.umn.edu/IPVSbid.

Science Page: PRRS incidence in status 4 sow farms

This is our Friday rubric: every week a new Science Page from the Bob Morrison’s Swine Health Monitoring Project. The previous editions of the science page are available on our website.

This week,  we are sharing a report by the MSHMP team on PRRS incidence in status 4 sow farms.

Key points

  • In the last 9 years, on average 10.2% (Range 3.7% – 22%) of status 4 farms have had a PRRS outbreak during the MSHMP season and in the 2017-2018 season, the cumulative incidence (July to April) is 9.6%.
  • The lowest PRRS incidence was observed during the 2013/2014 PRRS season; the year that PED entered the US.
  • PRRS incidence in status 4 farms during the current MSHMP season is not higher than the ones observed in the previous MSHMP seasons.

Reminder: Status 4 sow farms are the farms that considered negative both in shedding and exposure status in the classification document published by the AASV.

Objective

Has there been an increase in PRRS outbreaks incidence in status 4 sow farms?

Method

PRRS incidence in status 4 farms from 2009 to April 2018 was compiled and compared with the current MSHMP year using Fisher’s Exact test.

Results

During the current MSHMP year (July 2017- April 2018), 27 status 4 farms have had a PRRS outbreak (6.9% incidence). The average incidence of status 4 farms from 2009 to April 2018 was 9.6%. However, PRRS incidence have varied greatly among years (figure 1). PRRS incidence had its minimum value during the 2013/2014 MSHMP season with a 3.4%. This coincides with the year that porcine epidemic diarrhea virus (PEDv) entered the US.

When comparing the incidence during the 2017/2018 MSHMP year with the incidence observed during the 2015/2016 MSHMP year, a borderline significant difference (p=0.06) was observed.

PRRS incidence in status 4 sow farms
Figure 1. Percentage of PRRS incidence in Status 4 farms by year (July-April)

Summary

PRRS incidence in status 4 farms (July 2017 –April 2018) was overall similar to previous years, although slightly higher than July 2016-April 2017, and significantly lower than July 2015-April 2016. Other factors, such as region, may be contributing to the
perception of increased PRRS incidence in status 4 farms.Exploring these factors may help explain the perception of increased
incidence.

Remembering Bob, one year later

Bob_Morrison

This week marks the first anniversary of the loss of Dr. Bob Morrison. Dr. Morrison was killed in a tragic car accident in the Czech Republic in May 2, 2017.
In that same accident, we also lost Pam Wetzell and Deb Spronk, spouses of our dear friends Dr. Gordon Spronk and Dr. Tom Wetzell. We remember them in many ways especially for their kindness and love of life.

Bob was a mentor, teacher, colleague, friend and inspirational leader to many of us.

We remember Bob for his kindness, integrity, fertile mind, dedication to his students, peers and the swine industry, and for his passion to instill in others to do work that matters.

Bob is dearly missed and continues to be an inspiration to many of us.

Rest in peace Bob,

The Swine Faculty at the University of Minnesota