How dangerous is Mycoplasma infection for rats? - briefly
Mycoplasma infection can lead to serious respiratory illness, weight loss, and high mortality rates in rats, particularly in immunocompromised or stressed populations. Early detection and appropriate antibiotic therapy are critical to reduce its impact.
How dangerous is Mycoplasma infection for rats? - in detail
Mycoplasma organisms, especially Mycoplasma pulmonis, are common respiratory pathogens in laboratory and pet rats. Infection typically begins in the upper airway, spreads to the lungs, and may involve the urogenital tract. Clinical manifestations range from subclinical carriage to severe pneumonia, arthritis, otitis and reproductive failure.
Pathogenesis and clinical impact
- Colonization of the nasopharynx leads to epithelial damage, facilitating secondary bacterial invasion.
- Pulmonary involvement produces dyspnea, nasal discharge, cough and weight loss.
- Articular infection causes swollen, painful joints, limiting mobility.
- Reproductive lesions include uterine inflammation and reduced litter size.
Morbidity and mortality
- Morbidity rates in infected colonies often exceed 30 %, with higher values in stress‑prone or immunocompromised groups.
- Mortality is usually low in adult rats but can reach 20–40 % in neonates and pregnant females due to secondary infections and septicemia.
Transmission
- Direct contact through aerosolized secretions is the primary route.
- Indirect spread occurs via contaminated bedding, equipment, and personnel gloves.
- Vertical transmission from dam to offspring has been documented.
Diagnosis
- Culture on specialized mycoplasma media yields colonies after 5–7 days.
- Polymerase chain reaction (PCR) provides rapid, sensitive detection from nasal swabs or tissue samples.
- Serology (ELISA) identifies exposure but does not distinguish active infection.
Therapeutic options
- Tetracyclines (e.g., doxycycline) and macrolides (e.g., tylosin) reduce bacterial load; treatment courses last 7–14 days.
- Antibiotic resistance is emerging; susceptibility testing is advisable before therapy.
- Supportive care includes fluid therapy, warm environment and nutritional supplementation.
Preventive measures
- Quarantine new arrivals for at least 4 weeks, testing with PCR before integration.
- Implement strict barrier protocols: dedicated cages, autoclaved bedding, regular disinfection with agents effective against mycoplasmas (e.g., 70 % ethanol, quaternary ammonium compounds).
- Maintain low population density and reduce stressors (crowding, temperature fluctuations) to limit susceptibility.
Research implications
- Mycoplasma infection can confound experimental outcomes by altering immune responses, respiratory physiology and behavior.
- Regular health monitoring programs are essential for maintaining data integrity in studies involving rodents.
Overall, Mycoplasma infection poses a moderate to high health risk for rats, especially in dense or stressed populations, and can significantly affect both animal welfare and scientific results if left uncontrolled.