July 2017 – Swine in Minnesota

Infection dynamics and genetic variability of Mycoplasma hyopneumoniae in self-replacement gilts

This is a new research paper from the MycoLab under Dr. Maria Pieters’ supervision. In this study, the group looked at the infection dynamics and genetic variability of Mycoplasma hyopneumoniae in self-replacement gilts, in 3 positive herds. Serum samples were taken from the gilts at 150 days of age onward and laryngeal swabs were collected from the gilts and their progeny.

Highlights of this project

Genetic variability of M. hyopneumoniae was evaluated using MLVA typing.
The highest M. hyopneumoniae prevalence in gilts was detected at 150 days of age.
Detection patterns for M.hyopneumoniae were different among farms.
Genetic variability was identified within and among farms.

Abstract:

The aim of this study was to assess the longitudinal pattern of M. hyopneumoniae detection in self-replacement gilts at various farms and to characterize the genetic diversity among samples. A total of 298 gilts from three M. hyopneumoniae positive farms were selected at 150 days of age (doa). Gilts were tested for M. hyopneumoniae antibodies by ELISA, once in serum at 150 doa and for M. hyopneumoniae detection in laryngeal swabs by real time PCR two or three times. Also, 425 piglets were tested for M. hyopneumoniae detection in laryngeal swabs. A total of 103 samples were characterized by Multiple Locus Variable-number tandem repeats Analysis. Multiple comparison tests were performed and adjusted using Bonferroni correction to compare prevalence of positive gilts by ELISA and real time PCR. Moderate to high prevalence of M. hyopneumoniae in gilts was detected at 150 doa, which decreased over time, and different detection patterns were observed among farms. Dam-to-piglet transmission of M. hyopneumoniae was not detected. The characterization of M. hyopneumoniae showed 17 different variants in all farms, with two identical variants detected in two of the farms. ELISA testing showed high prevalence of seropositive gilts at 150 doa in all farms. Results of this study showed that circulation of M. hyopneumoniae in self-replacement gilts varied among farms, even under similar production and management conditions. In addition, the molecular variability of M. hyopneumoniae detected within farms suggests that in cases of minimal replacement gilt introduction bacterial diversity maybe farm specific.

Access to the full version of the paper

Science Page: Are the farms that broke with PED the same?

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 proud to introduce a new chart in the Morrison’s Swine Health Monitoring Project. This new addition will be able to answer a common question regarding PEDV outbreaks:

Are the farms currently breaking with PEDV the same than the ones which broke in the past?

To interpret the figure, follows these steps.

Horizontal axis represents all the farms that borke with PEDV during the season 2016/2017, with each tick representing an individual farm
Vertical axis shows the previous seasons with 2016-2017 on top and 2012-2013 at the very bottom.
The color of the cell (year : farm) represents the number of outbreaks experienced; darker blue meaning more outbreaks.

Here is the example of this chart presented this week:

MSHMP PEDV chart — Outbreak history of farms that broke during the 2016-2017 season.

Key points:

The farms that break with PEDV do not appear to have a history of PEDV infections in the prior season.

Of the farms that broke during the 2016/17 season, only 5 (6.5%) of them had outbreaks during the previous season and 43 (56.6%) of them had broken at some point since 2013.

Only one farm has had an outbreak every year since the beginning of the epidemic in the US (season 2013/14).

The full report is available.

Dr. Cesar Corzo appointed as new Leman Chair in swine health and productivity

The University of Minnesota, College of Veterinary Medicine is happy to announce that Dr. Cesar Corzo has accepted an appointment to the Allen D. Leman Chair in Swine Health and Productivity effective October 2, 2017. The appointment is considered one of the most prestigious faculty positions in the world involving swine medicine. Corzo was selected following an international search.

Corzo has worked for Pig Improvement Company (PIC) since 2012, most recently as the manager of Latin America Health Assurance and Services Team. The focus of his recent work has been on the emergence of Senecavirus A in Colombia, investigating the likelihood of infection of breeding stock during transit, and strategies for monitoring PRRS and Mycoplasma hyopneumoniae naïve populations of pigs with current serologic tests.

The Leman Chair appointment returns Corzo to the University where he earned his Ph.D. in 2012. He also holds a Master’s from the University of Guelph, and his DVM from La Salle University in Bogota, Colombia. His career also includes a three-year term with Elanco Animal Health.

In his new role, Corzo intends to focus on current industry challenges including personnel turnover and biosecurity compliance, control of endemic bacteria and optimization of antimicrobial usage.Corzo will play a major role in the Swine Health Monitoring program.

The Leman Chair in Swine Health and Productivity was created in 1995 to honor the career of Allen D. Leman. Those appointed to the chair serve for five years and are expected to significantly influence the swine industry’s adaptation to change. The individual also is expected to act as a catalyst for innovation and change within the University of Minnesota swine faculty.

Science Page: MSHMP Annual Summary

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 project runs from July 1st to June 30th so the year 2016-2017 just ended. Below are listed the main point for this year, more details can be found in the full report.

This year the Swine Health Monitoring Project was struck by the sudden and unexpected loss of Bob Morrison in a car accident in Prague. This was a major setback for the group and is a difficult challenge to overcome. However, we received the support of the industry to continue carrying on Bob’s legacy. Since last May the SHMP was renamed after him to Dr. Morrison’s SHMP (MSHMP).

Key points from this week edition:

Monitoring pathogens
- PRRS incidence (26%) remained stable over the last 2 years.
- PEDv incidence remained low (7%), at the same level as last year.
- Seneca Valley virus incidence appears to have a seasonal pattern.
- Monitoring of VDL atypical CNS cases has been restarted.
Analyzing PRRS virus sequences
- It appears that there are several characteristic features that would signal emerging PRRSv strains, which may be used for early detection of significant emerging events.
- Analyzed sequences coming from 3 systems to detect new emerging strains on a monthly basis.
Capturing movement data and incorporating into data management capacity
- Developed an app to capture truck movement.
- Tested a first version of the app.
- A second improved version will be tested shortly.
Expanding enrollment
- Added 4 production companies.
- Currently 33 systems with 1,092 sow farms & 2.96 million sows.
- 161 non participants receive weekly report.

Best Practices to manage seasonal infertility

Summer is here and for swine producers, this can be the start of seasonal infertility which is characterized by decreased breeding and farrowing performances in swine usually occurring in late-summer and/or early fall. How can it be prevented?

Dr. Perle Boyer from the University of Minnesota compiles in this month’s column for the National Hog Farmer the measures you can take to minimize seasonal effects on reproductive performances.

Seasonal infertility can affect both males and females. We tend to focus on the dam but boars should also be monitored during summer as the consequences of heat stress on semen quality can last up to several weeks in some cases.

Among the 5 tips in the list, keeping the pigs cool during the warmer month is certainly a priority. Remember that an adult neutral temperature is between 64F and 68F. Above that, heat stress can impair the animals’ performances. Additionally, making sure that the sows keep eating both during the lactation and during the days post-weaning has yield positive results for the following pregnancy.

Further advice can be found in the full article on seasonal infertility.