Detection of Mycoplasma hyopneumoniae in naturally infected gilts over time

A longitudinal study to assess Mycoplasma hyopneumoniae natural infection in gilts

This study was conducted by Dr. Karine Takeuti under the supervision of Dr. Maria Pieters from the University of Minnesota, College of Veterinary Medicine. The objective was to sample replacement gilts from 20 days of age until the day before weaning to detect Mycoplasma hyopneumoniae . Laryngeal swabs, tested by PCR, were taken every 30 days at a Mycoplasma positive sow farm. Therefore, the animals were naturally infected.

Gilts were found positive at 110 days, no detection in piglets

11.4% of the gilts were found positive at 110 days whereas all the previous samples came back negative. Positive results peaked at 140 days when 36.4% of the samples were positive for Mycoplasma hyopneumoniae. 27.3% of the gilts got positive results twice or more during the sampling period but 18.2% of the animals remained negative for the duration of the study.  All of the 220 piglets samples were also negative.

Takeuti longitudinal gilt mycoplasma hyopneumoniae 2017
Abstract

Mycoplasma hyopneumoniae causes a chronic respiratory infection in pigs and its transmission occurs mainly by direct contact and by vertical transmission (sow-to-piglet). The objective of this study was to assess the detection dynamics and persistence of M. hyopneumoniae natural infection in replacement gilts. Forty-four twenty-day-old gilts were selected from a M. hyopneumoniae positive farm and followed up to one day prior to their first weaning. Laryngeal swabs were collected every 30 days, starting at day 20, for M. hyopneumoniae detection by real-time PCR, resulting in 12 samplings. Piglets born to selected females were sampled via laryngeal swabs one day prior to weaning to evaluate sow-to-piglet transmission. The M. hyopneumoniae prevalence was estimated at each one of the 12 samplings in gilts and a multiple comparison test and Bonferroni correction were performed. Bacterial detection in gilts started at 110 days of age (doa) and a significant increase (p < 0.05) occurred at 140 doa. The M. hyopneumoniae prevalence remained above 20% from 140 to 230 doa, decreasing thereafter. However, it did not reach 0% at any sampling after 110 doa. In this study, M. hyopneumoniae was not detected in piglets sampled prior to weaning. The M. hyopneumoniae detection pattern showed that in natural infections, gilts were positive for M. hyopneumoniae for one to three months, but occasionally long-term detection may occur. Moreover, the lack of M. hyopneumoniae detection throughout the study in 18.2% of gilts indicated the existence of negative subpopulations in positive herds.

Link to the entire article

What does antimicrobial-resistant bacteria really mean?

Antimicrobial resistance is an expression that everyone in swine production has heard at least once but what does it really mean?  How are you as a producer or veterinarian affected?

Villalta NHF antimicrobial resistance 2017.gif

In this column for the National Hog Farmer, Dr. Carles Vilalta explains that beyond the definition of a bacterium that is not affected by an antimicrobial, there are two different approaches to think about resistance:

  • One is determined by the Minimal Inhibitory Concentration or MIC, which records the minimum medicine concentration required to stop the growth of the bacteria.
  • The other focuses on the presence of genes enabling the bacterium to counteract the effect of the antimicrobial.

These genes are usually present in a sub-population of bacteria called mutants. The video below created by Harvard Medical School shows how these mutants can develop, adapt, and survive the highest antimicrobial concentrations. (video length < 2min)

 

 

Science page: Creating really strong passwords

This is our Friday rubric: every week a new Science Page from the Bob Morrison’s Swine Health Monitoring Project.

Last week, we explained why we took the decision to change the name of the project to honor Bob and his dedication to the swine industry. The project continues, carrying his legacy.

Key points from this week edition:

  • Computer processing power keeps increasing at an alarming rate, allowing hackers to greatly increase their password cracking capabilities.
  • Hackers’ password cracking tools can crack weak passwords in no more than a couple of hours of execution. The same tools will take millions of years to crack a strong password.
  • Whenever password cracking is mentioned in this article, it should be assumed that the password is encrypted using a strong cryptographic hash algorithm such as scrypt: http://www.tarsnap.com/scrypt.html

So what makes a strong password in the end? Read our full paper on the topic.

Science Page: Bob Morrison’s legacy

Bob_MorrisonThis is our Friday rubric: every week a new Science Page from the Swine Health Monitoring Project. The previous editions of the science page are available on our website.

This week, the Science Page honors Dr. Robert Morrison, the founder and leader of the Swine Health Monitoring Project.

Bob’s unique talent for creating relationships that advanced the swine industry culminated in the creation of the Swine Health Monitoring Project (SHMP), one of the initiatives that Bob carried with pride. […] As it evolved, the SHMP changed names several times but many in the industry simply refer to it as “Bob’s project”. For that reason, and to give the just recognition he deserves, we have decided to renam the project to “Dr. Bob Morrison’s SHMP” (MSHMP).

Update of Jeanie’s situation on her Caring Bridge web page

A lot of you are asking for news and updates of the situation in Prague, or how you can help. Everything is now centralized in a Caring Bridge web page for Jeanie. We are keeping the Morrison, Spronk, and Wetzell families in our thoughts and wish Jeanie a full and quick recovery.

Dr. Morrison’s wife, Jeanie no longer in life threatening condition

We are trying to give you a daily update on the situation regarding the auto accident that happened in Prague on Tuesday and lead to Dr. Morrison’s passing.

As of today, Jeanie Morrison, Dr. Morrison’s wife, is no longer in a life-threatening condition said the doctors in charge of her recovery. We do not have any further information but the Morrison family is in the process of creating a online information page to provide updates on Jeanie’s situation. We will add the link here when it is available.

Thank you everyone for your support.

Edit: The Caring Bridge web page is here.

Passing of Dr. Robert Morrison, colleague, friend, and international leader in the swine industry

Bob_Morrison
Dr. Bob Morrison

The University of Minnesota College of Veterinary Medicine is mourning the death of Dr. Robert Morrison, a faculty member in its Department of Veterinary Population Medicine.  Dr. Morrison, his wife and several companions were involved in an auto accident north of Prague in the Czech Republic.  They were traveling prior to attending a swine health management conference in Prague.  “Dr. Morrison was an international leader in the swine industry,” says Dr. Trevor Ames, dean of the college. “This is a tragic loss for the strong team of students and faculty that Bob helped us build.  Our thoughts and prayers are with the Morrison family.”

Dr. Morrison was hired by the University of Minnesota in 1986 and recently launched the Swine Health Monitoring Project, which provides weekly reports on the health status of over 50% of the U.S. sow herds.  Dr. Morrison also coordinated two internationally-respected swine health management conferences: the St. Paul, MN-based Allen D. Leman Swine Conference and the Leman China Conference in Nanjing, China.  The conferences are named for UM professor Dr. Al Leman, who served as Dr. Morrison’s graduate advisor.