Effect of litter aggregation and pooling on detection of PRRSv in piglet processing fluids

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.

The Science Page this week was written by the MSHMP team and covers pooling of processing fluids. A more detailed report can be found on the blog. Currently, a study to evaluate the number of negative processing fluids to declare a farm stable is ongoing. If you are interested in participating in this study, contact Dr. Juan Sanhueza (jsanhuez-at-umn-dot-edu).

Continue reading “Effect of litter aggregation and pooling on detection of PRRSv in piglet processing fluids”

Best of Leman 2018 series #9: K. VanderWaal – Can we predict PRRS and PED outbreaks?

We launched a new series on the blog last year. Once a month, we are sharing with you a presentation given at the Allen D. Leman swine conference, on topics that the swine group found interesting, innovative or that lead to great discussions.

We can find all of the presentations selected from last year’s conference on the blog here.

Our ninth presentation is from Dr. Kim VanderWaal, our colleague at the University of Minnesota, who gives us a glimpse into a future when producers might be able to know when their farms are at risk of disease outbreaks.

Continue reading “Best of Leman 2018 series #9: K. VanderWaal – Can we predict PRRS and PED outbreaks?”

Assessing internal personnel movements in swine farms to help direct PRRS control and elimination efforts

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 the preliminary results of a study conducted by Dr. Andreia Arruda at Ohio State University.

Key points

  • Newly developed beacon-sensing technology can be used to better understand within-farm people movement; and particularly better quantify potentially “risky” movements in PRRS positive herds during control/ elimination efforts.
  • Preliminary data analysis showed that an increase in commonly referred to “risky” movements (e.g. from loading areas/ nurseries to other parts of the farm) was associated with a decrease in number of pigs weaned per sow; and an increase in pre-weaning mortality.
Continue reading “Assessing internal personnel movements in swine farms to help direct PRRS control and elimination efforts”

Best of Leman 2018 series #3: J.Angulo – Understanding PRRSV infection dynamics in growing pigs in control and elimination programs

We launched a new series on the blog last year. Once a month, we are sharing with you a presentation given at the Allen D. Leman swine conference, on topics that the swine group found interesting, innovative or that lead to great discussions.

We can find all of the presentations selected from last year’s conference on the blog here.

Our third presentation for this year is from Dr. Jose Angulo from Zoetis and Dr. Paul Yeske from Swine Vet Center regarding PRRS infection dynamics in growing pigs.

Click on the image below to see his presentation at the conference:


Breed-to-wean farm factors associated with influenza A virus infection in piglets at weaning

A scientific article written by Dr. Fabian Chamba Pardo when he was doing his PhD in the Torremorell lab was recently published on the journal of Preventive Veterinary Medicine. The study presented aimed to look at the various factors influencing the influenza infection status of piglets at weaning.

Highlights

  • Sow vaccination decreased influenza infections in piglets at weaning.
  • Influenza positive gilts at entry were associated with positive piglets at weaning.
  • More work is needed to assess herd closure, gilt isolation and gilt vaccination.

83 farms from 2 different pig production companies and located in Iowa, Minnesota and South Dakota were enrolled in this study. Samples were collected at weaning on a monthly basic for a little less than 6 years as part of routine surveillance programs. The majority of farms submitted 4 oral fluid samples per month but some collected nasal swabs or oro-pharyngeal swabs.

23% of the samples tested positive for influenza allowing the collection of 173 hemagglutinin sequences. In the H1 hemagglutinin subtype, isolates were 93.8% to 99% similar between each other and 94.3% to 97.4% similar to the vaccine strains. The largest discrepancy was found in the delta 1 clade. In the H3 hemagglutinin subtype, isolates were 95.9 to 99.7% similar among each other and 997.3% to 97.5% similar to the vaccine strains.

influenza factors for piglet positive at weaning

The influenza status of the piglets at weaning was influenced by several factors.

Seasons and vaccination status of the sows against influenza influenced piglet infection status at weaning. Indeed, sow influenza vaccination was significantly associated  with a decreased probability of piglets testing influenza positive at weaning. Both whole-herd and pre-farrow vaccination protocols were better compared to no vaccination and there were no differences between both protocols. Additionally, having influenza positive gilts at entry increased the probability of detecting positive piglets at weaning.

Among all the factors evaluated, sow influenza vaccination and gilt influenza status at entry were the only factors associated with influenza in piglets at weaning in Midwestern breed-to-wean farms.

Abstract

Breed-to-wean pig farms play an important role in spreading influenza A virus (IAV) because suckling piglets maintain, diversify and transmit IAV at weaning to other farms. Understanding the nature and extent of which farm factors drive IAV infection in piglets is a prerequisite to reduce the burden of influenza in swine. We evaluated the association between IAV infection in piglets at weaning and farm factors including farm features, herd management practices and gilt- and piglet-specific management procedures performed at the farm. Voluntarily enrolled breed-to-wean farms (n = 83) agreed to share IAV diagnostic testing and farm data from July 2011 through March 2017 including data obtained via the administration of a survey. There were 23% IAV RT-PCR positive samples of the 12,814 samples submitted for IAV testing within 2989 diagnostic submissions with 30% positive submissions. Among all the factors evaluated (n = 24), and considering the season-adjusted multivariable analysis, only sow IAV vaccination and gilt IAV status at entry significantly reduced (p-value<0.05) IAV infections in piglets at weaning. Results from this study indicate that veterinarians and producers could manage these identified factors to reduce the burden of influenza in piglets prior to wean and perhaps, reduce the spread of IAV to other farms and people.

Read the entire publication on the journal website.