Mycoplasma Detection

Introduction

Mycoplasma Detection is the process of determining whether a product or article is contaminated with, or has been produced by, mycoplasma. Mycoplasma are the smallest known motile organisms and can cause serious economic losses for the livestock industry.

Detection Methods

1. Physical Examination

Idiopathic lesions are identified in animals that may indicate infection with mycoplasmas. Lesions suggestive of mycoplasmal disease include mouth abscesses, sores in the nose, patches on the skin (e.g. scabs or scurf), blisters and ulcers on the skin, pyoderma, and otitis media. Common identification methods include fecal samples, throat and nasal swabs, trachea, conjunctiva, and tissue samples (e.g. lung tissue).

2. Culture of Mycoplasma

An important aspect of mycoplasma detection is isolating the bacterium. Mycoplasmas are fastidious organisms that require specific culture media to grow properly. Multiple media formulations and conditions (e.g. heat treatment, specific temperature, salinity, pH) exist, with some media being more appropriate than others based on the mycoplasmal species being examined. Mycoplasma are motile organisms that are susceptible to low-level chemical disinfectants such as chlorine and iodine compounds. For example, chlorination of water is an effective method for eliminating mycoplasma from water supplies. Disinfection, however, will not eliminate mycoplasmal infections in the absence of proper disinfection measures.

3. Indirect Hoechst Stain.

The indirect Hoechst stain, a fluorescent DNA dye, is a simpler method that produces results comparable to the more difficult direct immunofluorescence test. It involves staining a section of tissue with the DNA dye and then examining it under UV light. If mycoplasma are present, nuclear fluorescence will be present in infected cells.

4. PCR Methods

PCR can be used to amplify and then detect mycoplasmal DNA from tissue, urine, or feces. The presence of mycoplasma can be confirmed by detecting the presence of mycoplasmal DNA on a PCR-based test.

Conclusion

Although mycoplasmas are very small microorganisms and difficult to detect, the combination of the five methods above typically confirms diagnosis of these organisms in livestock. Mycoplasmas are ubiquitous, however, and can exist outside of animals (e.g. water supply). Therefore, always be cautious when handling mycoplasma-containing samples as they can be spread to other areas in a laboratory environment.