Editorial Type:
Theriogenology

Development of a broad-range quantitative polymerase chain reaction assay to detect and identify fungal DNA in equine endometrial samples

Ryan A. Ferris Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80521.

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Katy Dern Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80521.

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Julia K. Veir Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80521.

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Jennifer R. Hawley Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80521.

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Michael R. Lappin Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80521.

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Patrick M. McCue Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80521.

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 DVM, PhD
DOI:
https://doi.org/10.2460/ajvr.74.1.161
Volume/Issue:
Volume 74: Issue 1
Online Publication Date:
01 Jan 2013
Restricted access
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Abstract

Objective—To develop a broad-range 28S ribosomal DNA quantitative PCR (qPCR) assay for detection of fungal DNA in equine endometrial samples.

Sample—12 fungal samples from a clinical diagnostic laboratory and 29 samples obtained from 17 mares.

Procedures—The qPCR assay was optimized with commercially acquired fungal organisms and validated with samples obtained from the clinical diagnostic laboratory. Subsequently, 29 samples from 17 mares suspected of having fungal endometritis were evaluated via the qPCR assay and via traditional fungal culture and endometrial cytology. Amplicons from the qPCR assay were subjected to genetic sequencing to identify the organisms.

Results—The qPCR assay theoretically had a detection threshold of 2 organisms of Candida albicans. Fungal DNA was amplified from all 12 fungal samples from the commercial diagnostic laboratory. Fungal identification by use of genetic sequencing was successful for 34 of 36 amplicons from the 12 samples assayed. A fungal agent was identified via qPCR assay and genetic sequencing in all 12 samples; in contrast, a fungal agent was identified in only 8 of 12 samples via standard fungal culture and biochemical analysis. The qPCR assay detected fungal DNA in samples from 12 of 17 mares suspected of having fungal endometritis.

Conclusions and Clinical Relevance—A rapid, sensitive, and repeatable qPCR assay was developed for detection of fungal DNA from equine endometrial samples. The qPCR may prove to be clinically useful as an adjunct to microbial culture and cytologic examination to provide identification of fungal organisms in a timely manner.

Abstract

Objective—To develop a broad-range 28S ribosomal DNA quantitative PCR (qPCR) assay for detection of fungal DNA in equine endometrial samples.

Sample—12 fungal samples from a clinical diagnostic laboratory and 29 samples obtained from 17 mares.

Procedures—The qPCR assay was optimized with commercially acquired fungal organisms and validated with samples obtained from the clinical diagnostic laboratory. Subsequently, 29 samples from 17 mares suspected of having fungal endometritis were evaluated via the qPCR assay and via traditional fungal culture and endometrial cytology. Amplicons from the qPCR assay were subjected to genetic sequencing to identify the organisms.

Results—The qPCR assay theoretically had a detection threshold of 2 organisms of Candida albicans. Fungal DNA was amplified from all 12 fungal samples from the commercial diagnostic laboratory. Fungal identification by use of genetic sequencing was successful for 34 of 36 amplicons from the 12 samples assayed. A fungal agent was identified via qPCR assay and genetic sequencing in all 12 samples; in contrast, a fungal agent was identified in only 8 of 12 samples via standard fungal culture and biochemical analysis. The qPCR assay detected fungal DNA in samples from 12 of 17 mares suspected of having fungal endometritis.

Conclusions and Clinical Relevance—A rapid, sensitive, and repeatable qPCR assay was developed for detection of fungal DNA from equine endometrial samples. The qPCR may prove to be clinically useful as an adjunct to microbial culture and cytologic examination to provide identification of fungal organisms in a timely manner.

Contributor Notes

Address correspondence to Dr. Ferris (rferris@colostate.edu).
Cover American Journal of Veterinary Research
American Journal of Veterinary Research
Publication Date:
01 Jan 2013
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