PRRS – Swine in Minnesota

Review of Chart 3: PRRS incidence rate by status at break

Key Points

Incidence rate takes into account the time a farm is at risk for disease.
Chart 3 incidence rate has replaced incidence risk by status which did not account for a farm’s contributed time at risk.
While incidence rate is less visually intuitive, it more accurately reflects PRRS outbreak rate by status.

Yearly incidence rate of PRRS per MSHMP Participating Production System

This week, the MSHMP team is sharing the yearly PRRS incidence rates in the 39 participating systems.

Keypoints

The average incidence rate for all systems during the entire period described was 0.27 PRRS outbreaks per farm per year.
The incidence rate of PRRS outbreaks within a system varies across years with some participants continuing to have lower incidences.

Understanding whether PRRS viruses in a neighborhood are closely related

This week, the MSHMP team is sharing results from a study looking at how related PRRSv ORF5 sequences from a same area are.

Key Points

28 space-time clustering of PRRSv based on producers’ routine molecular surveillance were identified in the course of 2010-2019.
Being inside or outside a space-time cluster significantly explains the genetic variability of most, but not all cases.
Assessing space, time, and genetic relatedness relationships in PRRSV transmission is complex, and overall trends might miss important case information.

Development of an automated model to capture and analyze whole-herd parameters associated with wean-to-finish mortality

This week, Dr. Linhares’s team from Iowa State University is proposing a model to analyze wean-to-finish mortality based on whole-herd parameters such as farrowing rate, PRRS status or even management factors.

Key Points

An automated model was developed to consolidate multiple data streams from weaning cohorts to their respective closeouts.
Sow farm productivity and health are highly associated with wean to finish mortality.
Sow farm-related data explained 74.1% of the variation observed on wean to finish mortality.

Best of Leman 2019 #3: Three systems views on PRRS decreasing incidence

A few days ago, we shared a report that PRRS incidence decreased in naive breed-to-wean farms. Interesting questions were brought forward by our readers so this month, we are sharing three practitioners’ experiences with PRRS in their systems: Dr. Tara Donova with the Hanor company, Dr. Jay Miller with The Maschhoffs, and Dr. Pete Thomas from Iowa Select Farms.