Improvements in Tritrichomonas foetus molecular testing. (July 2018)

• Record Type: Journal Article
• Authors: Ginter Summarell, Carly C.; Hairgrove, Thomas B.; Schroeder, Megan E.; Conley, Robert; Bounpheng, Mangkey A.
• Is Part Of: Journal of veterinary diagnostic investigation. Volume 30:Number 4(2018:Jul.)
• Page Start: 603
• Page End: 608
• Publication Date: 2018-07
• Subjects: Cows -- reverse-transcription quantitative real-time PCR -- smegma -- Tritrichomonas foetus; Veterinary medicine -- Diagnosis -- Periodicals; 636.0896075
• DOI: 10.1177/1040638718767943
• Languages: English
• ISSNs: 1040-6387

Abstract

Bovine trichomoniasis is a sexually transmitted disease that results in infertility, abortion, and calf age variability. To date, management strategies include testing for Tritrichomonas foetus and culling of infected males. Challenges associated with testing include cost of culture medium, time and labor burden of sample incubation and processing, and adverse effects of bacterial growth on detection sensitivity. To overcome these challenges, we developed a direct reverse-transcription quantitative real-time PCR (direct RT-qPCR) utilizing smegma, eliminating the use of culture medium. In an analysis of 166 field samples (56 positives and 110 negatives as determined using microscopic reading of cultures as the reference test), the direct RT-qPCR exhibited 100% diagnostic sensitivity and 100% specificity, whereas the currently employed qPCR (culture qPCR), which utilizes cultured samples, exhibited 95% diagnostic sensitivity and 100% specificity. Agreement between direct RT-qPCR and culture qPCR was 98%. Moreover, direct RT-qPCR identified 3 more positive samples and exhibited lower quantification cycle (Cq) values among positives by culture reading than did culture qPCR (direct RT-qPCR Cq range = 14.6–32.3 vs. culture qPCR Cq range = 18.7–37.4). The direct RT-qPCR enables simplified sample collection, elimination of culture medium, faster results, applicability in cows, and lower cost than culture qPCR.