A quick guide to Mycoplasma hyopneumoniae diagnostics

Sample types for early detection of Mycoplasma hyopneumoniae is a popular post on this blog. Dr. Pieters, head of the MycoLAb at the University of Minnesota created an online quick guide to help swine practitioners decide which sample type they should collect if they are looking for Mycoplasma hyopneumoniae.

This guide is available at http://z.umn.edu/MycoplasmaDiagnostics

Continue reading “A quick guide to Mycoplasma hyopneumoniae diagnostics”

Piglet gut microbiota: a potential determinant for M. hyopneumoniae susceptibility

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 by the MycoLab regarding piglet microbiota and its potential influence of M.hyopneumoniae susceptibility.

Key points

  • Early life gut microbiota could be a potential determinant in modulating susceptibility to chronic respiratory diseases such as enzootic pneumonia in pigs.
  • Increased abundance of short‐chain fatty acid producing bacteria in piglet gut was associated with decreased M. hyopneumoniae respiratory lesions.  
  • Understanding the function and composition of a ‘healthy’ pig gut microbiota would aid to successfully implement novel disease control strategies.
Continue reading “Piglet gut microbiota: a potential determinant for M. hyopneumoniae susceptibility”

Best of Leman 2018 series #2: M. Schwartz – A systems approach to M. hyopneumoniae elimination

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

We can find all of the presentations selected from last year’s conference on the blog here.

Our second presentation for this year is from Mark Schwartz from Schwartz Farms sharing their experience trying to eliminate Mycoplasma hyopneumoniae from their system.

Click on the image below to see his presentation at the conference:

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

Acclimation strategies in gilts to control Mycoplasma hyopneumoniae infection

Today we are sharing a review article regarding the acclimation strategies in gilts to control Mycoplasma hyopneumoniae infection published in Veterinary Microbiology by  the University of Barcelona in collaboration with Dr. Maria Pieters.

Key points

  • M. hyopneumoniae monitoring should be performed in incoming gilts and recipient herd.
  • Gilt acclimation against M. hyopneumoniae aids to maintain farm health stability.
  • Vaccination is the main strategy used to acclimate gilts in Europe and North America

Monitoring and diagnosis of M.hyopneumoniae

The article first covers how to assess the M. hyopneumoniae health status of the herd. Various methods of monitoring and diagnosis are detailed and compared with each other.

  • Most commonly used: M. hyopneumoniae antibody detection by ELISA but the interpretation of the results can be challenging.
  • Most useful technique: PCR on different respiratory tract samples.
  • No consensus on sample type to detect bacterial DNA in live pigs.

Classification of the herd based on incoming replacement and recipient herd

 

Proposed farm classification according to M. hyopneumoniae health status. (aELISA results (negative/positive) could depend on infection pattern in the farm and sampling time point.)

Classification


Clinical signs Lung lesions ELISA resulta PCR result
Negative Not observed Not observed Negative Negative
Provisional negative Not observed Not observed Positive Negative
Positive Subclinical infected I Not observed Not observed Positive/Negative Positive
Subclinical infected II Not observed Observed Positive/Negative Positive
Clinical affected Observed Observed Positive/Negative Positive

Prevention and control

Vaccination against M. hyopneumoniae, using commercial vaccines, is the most commonly used strategy to control its associated diseases in worldwide swine production systems.

However, since protection against M. hyopneumoniae infection by commercial vaccines is not complete, antimicrobial treatments are frequently required to control disease outcome. Several antibiotic classes are effective in reducing the incidence and severity of M. hyopneumoniae compatible lung lesions: macrolides, lincosamides, tetracycline, and fluoroquinolones among others.

Acclimation scenarios

Europe

The most common replacement origin used in Europe was external and that most respondents knew M. hyopneumoniae health status of replacement on arrival, being in most of the cases seropositive. Nevertheless, only 28% of respondents verified this theoretical M. hyopneumoniae status given as ELISA test results. Additionally, the most used strategy to acclimate gilt was vaccination alone (58%).

North America

Gilt Development Units are utilized to allow ample time to incoming gilt to gradually adopt the health status of the recipient herd. These acclimation facilities are in most of the cases continuous flow allowing an effective gilt exposure to M. hyopneumoniae. Gilt vaccination in North American swine industry was also recognized as the most common practice used at acclimation.

Natural exposure

Natural exposure was also used in both continents to help acclimate the incoming gilts to  M.hyopneumoniae. However, taking into account that pig-to-pig transmission of this bacterium has proven to be extremely slow , the ratio of infected and naïve gilts as well as the time of exposure are crucial and should be considered to achieve an effective exposure.

 

Abstract

Mycoplasma hyopneumoniae (M. hyopneumoniae) is the primary causative agent of enzootic pneumonia (EP), one of the most economically important infectious disease for the swine industry worldwide. M. hyopneumoniae transmission occurs mainly by direct contact (nose-to-nose) between infected to susceptible pigs as well as from infected dams to their offspring (sow-to-piglet). Since disease severity has been correlated with M. hyopneumoniae prevalence at weaning in some studies, and gilts are considered the main bacterial shedders, an effective gilt acclimation program should help controlling M. hyopneumoniae in swine farms. The present review summarizes the different M. hyopneumoniae monitoring strategies of incoming gilts and recipient herd and proposes a farm classification according to their health statuses. The medication and vaccination programs against M. hyopneumoniae most used in replacement gilts are reviewed as well. Gilt replacement acclimation against M. hyopneumoniae in Europe and North America indicates that vaccination is the main strategy used, but there is a current trend in US to deliberately expose gilts to the pathogen.