Establishment and application of TaqMan probe-based quantitative real-time PCR for rapid detection and quantification of Ichthyophthirius multifiliis in farming environments and fish tissues

Ichthyophthirius multifiliis, a pathogenic ciliate, is a crucial pathogen of freshwater fish and can result in severe economic loss in the aquaculture industry worldwide. It is necessary to develop a sensitive and accurate method for detecting I. multifiliis in farming environments and fish skin and gills to protect fishes from infection of the parasite due to a lack of both safe and effective treatment drugs. The present study established a new TaqMan probe-based quantitative PCR (qPCR) detection method targeting the coding region of the cathepsin L cysteine protease (ICP2) gene of I. multifiliis. The sensitivity, specificity, reproducibility and application for detection and diagnosis of the TaqMan probe-based qPCR method were evaluated. In addition, the linear model between the cycle threshold…