Science Page: Effective disease surveillance and response strategies depend on detailed swine shipment data

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 regarding the use of swine shipment data for effective disease surveillance by Drs. Amy Kinsley, Meggan Craft, Andres Perez, and Kim VanderWaal.

Key point:

  • A production system’s vulnerability to disease spread can be greatly reduced when selectively identifying a subset of farms as disease control targets.

What was done:

In this study, we used a network approach to describe annual movement patterns between swine farms in three multi-site production systems (1,063 farms) in the United States.

We measured:

  1. degree: number of farms to which a farm ships or receives pigs
  2. farm’s individual contribution to disease spread via its movements
  3. mean infection potential (MIP), which measures potential incoming and outgoing infection chains

What was found:

Removing farms based on their mean infection potential substantially reduced the potential for transmission of an infectious pathogen through the network when compared to removing farms at random, as shown by a reduction in the magnitude of R0 attributable to contact pattern.
The MIP was more efficient at identifying targets for disease control compared to degree and farm’s contribution to disease spread.

What does this mean?

By targeting disease interventions towards farms based on their mean infection potential, we can substantially reduce the potential for transmission of an infectious pathogen in the contact network, and performed consistently well across production systems.
Fine-scale temporal movement data is important and is necessary for in-depth understanding of the contact structure in developing more efficient disease

 

 

 

Best of Leman 2017 series #7: P. Yeske – Assessment of the likelihood of Mycoplasma hyopneumoniae lateral transmission

We launched a new series on the blog in October. Once a month, we are sharing with you a presentation given at the 2017 Allen D. Leman swine conference, on topics that the swine group found interesting, innovative or that lead to great discussions.

Our seventh presentation is by Dr. Paul Yeske from Swine Vet Center regarding the likelihood of lateral transmission of Mycoplasma hyopneumoniae.

To listen to this talk, please click on the image below.

Yeske Mycoplasma hyopneumoniae lateral transmission

NHF: Enteroids as in vitro model for ileitis

Our new contribution to the National Hog Farmer was written by Dr. Talita Resende, a PhD candidate at the University of Minnesota under the supervision of Dr. Connie Gebhart. Talita’s research focuses on swine ileitis and models to better understand its pathogen: Lawsonia intracellularis. Today, she explains how she uses enteroids.

The small intestine is largely responsible for nutrient digestion and absorption in the gastrointestinal tracts of pigs, but it is also an ideal colonization site for enteric pathogens. The investigation of the interactions between host and enteric pathogens can be conducted in vivo, or in vitro, with advantages and disadvantages for each of the models. Enteroids, small intestinal organoids, represent a new in vitro approach to investigate those interactions. But why are enteroids a new approach and what are their advantages in comparison to the current models?

Enteroids are three-dimensional structures originated from embryonic stem cells, induced pluripotent cells or adult stem cells from intestinal tissue. Therefore, they present all the cell types and a structural organization similar to crypts and villi found in the small intestine. This complex structure offers ideal conditions to investigate the mechanisms by which Lawsonia intracellularis causes proliferative enteropathy – also known as ileitis – in pigs.

Science Page: Sow Herd Filter Study

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 note from Dr. Cesar Corzo who is starting a study on sow herd filtration and recruiting herds. The MSHMP mission goes beyond collecting data regarding swine herd disease status, it also includes research projects that are relevant to the swine community.

Objectives of the study

The objectives of the study are to describe the occurrence of PRRSv in the filtered sow herd population within MSHMP and to assess the associations between farm-level factors and the introduction of PRRSv into filtered sow herds. The results of the study may guide practitioners and veterinarians to modify their management and biosecurity practices in filtered sow herds.

Who can enroll?

All filtered sow herds of MSHMP participants will be eligible for the study. The database will be used together with the PRRSv incidence measure to understand occurrence of PRRS before and after filters were installed. A survey has been created to collect farm specific data such as:

  • Date when herd was filtered
  • Type of ventilation (negative or positive)
  • Back draft prevention methodology
  • Type of pre-filter and filter
  • Pre-filter and filter replacement frequency
  • Number of barns and load outs
  • Audit frequency
  • Frequency of gilt introduction and weaning events
  • Regional density

If you are interested in participating, please contact Dr. Cesar Corzo at corzo(at)umn.edu

Senecavirus A publications in English and in Spanish

A fair part of our audience originates from Spanish-speaking countries. Our researchers appreciate your support and your interest in our work. Recently, Drs. Matthew Sturos and Fabio Vannucci published an article in the journal Albeitar regarding Senecavirus A and its tropism for reproductive organs.

A quick summary of the article that can be found online in open access:

Se trata de un virus patógeno emergente en el ganado porcino. En este artículo se proporciona información general sobre el virus y el conocimiento actual de la patogénesis y las características de la enfermedad.

For our English-speaking readers, we recommend a previous publication on this page also by Dr. Sturos called Natural and experimentally-induced Senecavirus A infections in boars.

Happy reading!