Best of Leman 2017 series #3: J. Lowe – Understanding cull sow movements in North America

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 third presented is from Dr. Jim Lowe from the University of Illinois on the movements of cull sows in North America and what it implies in terms of disease transmission.

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


Happy holidays to you and your loved ones!

Science page: Troubleshooting poor litter size using the National Swine Reproduction Guide

First, we would like wish you the happiest of holidays from all of us at the University of Minnesota, College of Veterinary Medicine.

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 how to troubleshoot poor litter size within a production system using the National Swine Reproduction Guide, a report by Sarah Bloomer at North Carolina State University.

Key points:

  • The National Swine Reproduction Guide (NSRG; U.S. Pork Center of Excellence, Des Moines, IA) is a valuable tool to help producers utilize data analysis to troubleshoot reproductive problems in a herd or farm.
  • Analysis of farrow-to-wean farms within a North Carolina production system revealed extended wean-to-service interval of first-parity sows and poor performance of second-parity sows. NSRG recommendations include reviewing lactation diet composition and first-parity sow lactation feed intake.

Reproductive data from nine farms within one production system from 2011 to 2015 were obtained. Average Total Number Born (TNB) for the production system was 12.4 piglets born per litter, yet litter size was lowest in second-parity sows. Greater than 24% of second-parity sows failed to achieve the decision boundary criteria of 11.5 TNB. Within first-parity sows, 73% of the contemporary groups had greater than 10% of their sows failing to return to estrus within 10 days of weaning.

NSRG recommendations.gif

The following recommendations to improve TNB and reduce Weaning-to-Service Interval  (WSI) were created following consultation of the NSRG:

  1. Limit cross-fostering onto first-parity sows
  2. Review lactation diet composition, particularly amino acid content;
  3. Identify methods to promote first-parity sow lactation feed intake. If economically
    feasible, farms may also consider breeding sows displaying estrus 7 and 8 days post-weaning on their next cycle.


Two UMN graduate students awarded at CRWAD

The first week-end of December was the Conference of Research Workers in Animal Diseases in Chicago. Several of the swine group graduate students were presenting their work and received an award.

NC1202 Student Award 3First, Frances Shepherd received the award for best oral presentation in the Enteric Diseases category for her presentation titled Variability and bioinformatic analysis of porcine rotavirus B and C illustrate potentially important immunological sites. Frances’ advisers are Dr. Douglas Marthaler and Dr. Michael Murtaugh.

AVEMP Student AwardsThen, Dr. Robert Valeris received the best poster award in the Veterinary Epidemiology and Preventative Medicine category for presenting Survival analysis of protocols for eradication of Mycoplasma hyopneumoniae in swine farms.

Join us in congratulating our students for their awards!


NHF: Processing fluids are effective for PRRSV diagnostics

This month in the National Hog Farmer, Drs. Carles Vilalta, Juan Sanhueza, and Montse Torremorell share a project instigated by the late Dr. Bob Morrison regarding the use of processing fluids to make a PRRSV diagnosis.

The improvement of sampling and diagnostics techniques has made sampling on the farm an easier task with the use of pooled serums or oral fluids samples for example.

One of the ways to get cheaper, more sensitive and quicker techniques would be to use routine chores, such as piglet processing, since castration and tail docking are part of the regular procedures in sow farms.

The goal of this study was to evaluate the accuracy of the processing fluids (the liquid accumulated at the bottom of the pail when farmers collect tails and testicles during routine procedures) by real-time polymerase chain reaction to assess PRRSV status in a sow herd.

The key points from the studies were:


Science page: Investigating PRRS summer outbreaks in the US

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 an investigation into PRRS summer outbreaks by Dr. Juan Sanhueza and the MSHMP team.

Key Points

  • Each year approximately 3% of the sow farms have a PRRS outbreak during the summer.
  • The incidence of summer PRRS breaks has been constant over the last 9 years.
  • There are geographical areas with higher or lower risk of summer breaks.
prevalence of summer PRRS outbreaks per year
Figure 1. PRRS summer outbreak incidence per year between 2009 and 2017.

A summer outbreak was defined as a PRRS case that happened between June 21st and September 21st of the year. The mean incidence of PRRS summer outbreaks was 3.2% between 2009 and 2017, ranging between 1.6% and 4.4%. The trend was stable among the years. (Figure 1) Not all areas are equal against summer outbreaks. Indeed, the region of Southern Minnesota – Northern Iowa is more at risk of outbreaks than others like Southern Iowa or Eastern North Carolina. (Figure 2)

areas with higer lower PRRS risk in the summer
Figure 2. Geographical areas with higher (red) and lower (blue) PRRSV incidence risk

Biosecurity measures against PRRSV should therefore be a concern all year round for swine producers!


The U of MN well represented at the NA PRRS Symposium

The first week-end in December is usually the time of the North American PRRS symposium. This year did not upset the tradition but this time, the conference was in collaboration with the National Swine Improvement Federation.

The 2017 NA PRRS meeting was dedicated to Dr. Bob Morrison.

The meeting was dedicated to our friend and colleague Dr. Bob Morrison. A memorial fellowship organized by Dr. Montse Torremorell (U of MN) and Dr. Joan Lunney (USDA) provided travel support to future scientists who wish to follow in his footsteps.

Stephen Gerike from the Pork Checkoff shared information on the state of pork products used in restaurant. Bacon represents 20% of products used but is still growing (+4% since last year).

Stephen Gerike shared the updated cooking recommendations for pork product.

 Overall, 82% of restaurant customers eat the same or larger amount of pork which is a good trend for the industry. Mr. Gerike also shared the efforts done by Pork Checkoff to convince consumers to not overcook their pork. Reminder: 145F is safe. “Cook your pork like you cook your steak!”


The University of Minnesota was well represented during the conference. Dr. Montse Torremorell moderated the Saturday morning session on PRRS in the field. Drs. Cesar Corzo, Carles Vilalta and Juan Sanhueza shared the updates on the Morrison Swine Health Monitoring Program as well as regarding the studies that they are involved with. Take away messages:

  • MSHMP is now collecting information from 50% of the sows in the United States.
  • Based on this data, 58% of the farms breaking with PRRSV today will break again within a year.
  • PRRS summer outbreaks happen and vary based on location (see figure below).
  • Farms take a longer time to reach stability after a summer outbreak (median 41.5 weeks)
  • Processing fluids can be used as a monitoring method for PRRS.

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Dr. Perle Boyer shared the launching of an online course designed in collaboration with Iowa State University regarding genetic resistance to PRRSV. The course will be open in Spring 2018 and is designed for swine health professionals, veterinarians and experts who want to know more about the Principles and application of genetics and genomics to improve animal health.