Mycoplasmosis in captive crows and robins from Minnesota

Area of Science:

• Avian microbiology
• Bacterial pathogenesis
• Molecular diagnostics

Background:

• Mycoplasma sturni is a recently identified bacterium.
• Previous reports linked M. sturni to conjunctivitis in European starlings, northern mockingbirds, and blue jays.
• The host range and transmission dynamics of M. sturni remain incompletely understood.

Purpose of the Study:

• To report the isolation of Mycoplasma sturni from an American crow with conjunctivitis.
• To develop and validate a sensitive molecular diagnostic assay for M. sturni detection.
• To investigate the presence of M. sturni in asymptomatic birds and assess genetic heterogeneity among isolates.

Main Methods:

• Isolation and identification of Mycoplasma sturni from clinical samples.
• Development and sensitivity testing of a nested-PCR assay for M. sturni.
• Random amplified polymorphic DNA (RAPD) analysis to assess genetic diversity of M. sturni isolates.
• Sampling of asymptomatic birds housed in proximity to infected individuals.

Main Results:

• Mycoplasma sturni was successfully isolated from a conjunctivitis-affected American crow.
• The nested-PCR assay demonstrated a sensitivity of 10 colony-forming units.
• M. sturni was detected in asymptomatic American crows, American robins, and a European starling.
• RAPD analysis revealed significant genetic heterogeneity among M. sturni isolates from different host species and within the American crow population.

Conclusions:

• Mycoplasma sturni can infect American crows and American robins, potentially without causing clinical disease.
• Nested-PCR is an effective tool for detecting Mycoplasma sturni in clinical and environmental samples.
• Genetic diversity exists within Mycoplasma sturni populations, suggesting complex evolutionary and epidemiological patterns.