Respiratory disease remains one of the most significant health and production challenges facing the poultry industry. Among the most economically important bacterial pathogens affecting commercial broilers, layers and breeders are Mycoplasma gallisepticum (MG) and Mycoplasma synoviae (MS). These highly contagious organisms can reduce flock performance, increase production costs and create ongoing biosecurity challenges if they are not detected and managed early.
Through EnvirocareVet, the dedicated veterinary diagnostics division of Envirocare Laboratory, we provide rapid, highly sensitive PCR testing for MG and MS to help veterinarians, poultry producers and integrators make informed disease management decisions. Molecular diagnostics enable early detection, support surveillance programmes and provide reliable results for flock health monitoring.
Understanding Mycoplasma gallisepticum (MG) and Mycoplasma synoviae (MS)
MG and MS are bacteria that lack a cell wall, making them biologically different from many other poultry pathogens. They spread through direct bird-to-bird contact, contaminated equipment and personnel, and can also be transmitted vertically from breeder hens to chicks through eggs.
Because infected birds may appear healthy while still carrying and spreading infection, Mycoplasma can circulate silently within a flock long before obvious clinical signs develop.
Mycoplasma gallisepticum (MG)
MG is one of the primary causes of chronic respiratory disease (CRD) in poultry and is commonly associated with:
- Coughing and sneezing
- Nasal discharge
- Conjunctivitis
- Swollen sinuses
- Airsacculitis
- Reduced weight gain
- Poor feed conversion
- Lower egg production
- Increased susceptibility to secondary bacterial infections such as Escherichia coli
The economic impact of MG extends beyond mortality, with reduced flock performance often representing the greatest financial loss.
Mycoplasma synoviae (MS)
Although MS may also cause respiratory disease, it is particularly recognised for causing infectious synovitis, resulting in:
- Swollen joints
- Lameness
- Reduced mobility
- Poor growth rates
- Decreased feed efficiency
Certain strains of MS have also been linked to eggshell apex abnormalities (EAA), leading to poor eggshell quality, increased egg downgrades and reduced profitability in commercial layer operations.
MG vs MS: What’s the Difference?
Although both organisms belong to the Mycoplasma family, they affect poultry differently.
| Mycoplasma gallisepticum (MG) | Mycoplasma synoviae (MS) |
|---|---|
| Primarily causes chronic respiratory disease | Causes respiratory disease and infectious synovitis |
| Frequently associated with airsacculitis | Commonly associated with swollen joints and lameness |
| Reduces growth and egg production | May cause eggshell abnormalities in layers |
| Increases susceptibility to secondary respiratory infections | Often affects mobility and feed conversion |
Both pathogens can occur together, making accurate laboratory diagnosis essential for selecting appropriate management and control strategies.
Why Early Detection Matters
Many Mycoplasma infections begin as subclinical infections. Birds may carry and spread the organism without showing obvious signs of illness, allowing infection to establish throughout the flock before production losses become noticeable.
Early diagnosis allows producers and veterinarians to:
- Identify infection before widespread clinical disease develops
- Reduce transmission within and between poultry houses
- Strengthen biosecurity interventions
- Improve treatment and vaccination strategies
- Minimise long-term production losses
- Protect breeder and layer performance
Routine laboratory monitoring is therefore an important component of modern poultry health programmes.
Why PCR Testing Is the Preferred Diagnostic Method
Traditional culture methods for Mycoplasma are technically demanding, require specialised laboratory conditions and may take several weeks to produce results. Because Mycoplasma organisms grow slowly and may be shed intermittently, culture alone can fail to detect infected birds.
Polymerase Chain Reaction (PCR) testing detects Mycoplasma DNA directly from clinical samples, providing a faster and more sensitive method of diagnosis.
EnvirocareVet’s molecular PCR testing offers:
- High sensitivity and specificity for MG and MS
- Rapid turnaround times
- Detection during the early stages of infection
- Accurate differentiation between Mycoplasma gallisepticum and Mycoplasma synoviae
- Reliable results for surveillance, outbreak investigations and routine monitoring
- Support for veterinary treatment and biosecurity decision-making
PCR has become the preferred diagnostic method for many poultry disease investigations because it enables earlier intervention and more effective disease control.
Sample Collection for MG & MS PCR Testing
Accurate laboratory results begin with appropriate sample collection. Depending on the clinical situation, commonly submitted samples may include:
- Tracheal swabs
- Choanal cleft swabs
- Oropharyngeal swabs
- Tissue samples from affected birds
- Samples collected during disease investigations or routine surveillance
Proper sampling and transport procedures help ensure the highest possible diagnostic accuracy. Producers are encouraged to consult their veterinarian or the EnvirocareVet team regarding the most appropriate sampling strategy for their flock.
Applications of MG & MS PCR Testing
MG and MS PCR testing forms an important part of comprehensive poultry health management programmes and can be used for:
- Routine flock monitoring
- Breeder flock surveillance
- Pre-placement health screening
- Investigation of respiratory disease outbreaks
- Disease tracing and epidemiological investigations
- Verification of flock health status
- Monitoring the effectiveness of disease control programmes
- Supporting veterinary treatment decisions
- Biosecurity and risk management programmes
Routine molecular testing provides valuable information that helps producers identify disease trends before significant production losses occur.
Supporting Poultry Biosecurity and Productivity
Effective biosecurity depends on rapid and accurate disease detection. By incorporating PCR testing into routine poultry health management, producers can make evidence-based decisions that protect flock health and improve production efficiency.
Benefits include:
- Earlier disease detection
- Reduced spread within and between production sites
- Improved bird welfare
- Better production performance
- Greater confidence in flock health reporting
- Support for industry best practices and veterinary compliance
Backed by the analytical expertise, quality systems and scientific credibility of Envirocare Laboratory, EnvirocareVet provides veterinary molecular diagnostics that poultry producers can rely on.
Contact EnvirocareVet Laboratory
For trusted molecular diagnostics supporting poultry health, disease surveillance and biosecurity programmes, contact EnvirocareVet.
📩 Email: info@envirocarelab.co.za
📞 Tel: +27 18 294 4283
🌐 Website: https://envirocarelab.co.za/
EnvirocareVet – Advancing poultry health through trusted molecular diagnostics.
References
- World Organisation for Animal Health (WOAH). Terrestrial Manual: Mycoplasma gallisepticum and Mycoplasma synoviae.
- Food and Agriculture Organization (FAO). Poultry Development Review: Poultry Health and Disease Control.
- Merck Veterinary Manual. Mycoplasmosis in Poultry.
- Ley, D. H. (2003). Diseases of Poultry (11th Edition): Mycoplasma gallisepticum Infection.
- Kleven, S. H. (2008). Control of Avian Mycoplasma Infections in Commercial Poultry. Avian Diseases.
- Ewing, M. L., & Kleven, S. H. (2013). Comparison of Diagnostic Methods for Detection of Mycoplasma gallisepticum and Mycoplasma synoviae.
- South African Poultry Association (SAPA). Poultry Disease Management and Biosecurity Guidelines.
