Molecular detection of three intestinal cestode species (Raillietina echinobothrida, R. tetragona, R. cesticillus) from poultry in Thailand

Abstract

Cestodes belonging to the genus Raillietina are a major veterinary health problem affecting the poultry industry, particularly chickens (Gallus gallus domesticus) and ducks (Anas playtrhynchos domesticus). The traditional method for accurately detecting this cestode based on their morphological characteristics is rather difficult due to the large number of morphological similarities. Consequently, this study aimed to develop specific primers for R. echinobothrida, R. tetragona, and R. cesticillus detection that could be used to indicate epidemic areas for protection and infection control. Specific primers were manually designed based on the internal transcribed spacer 2 region and validated, establishing the optimal temperature, final concentration in PCR mixture, specificity, and sensitivity of each primer set. The results showed that the primers amplify specific species without cross-amplifying other parasites and hosts. The PCR products were about 473, 352, and 397 bp long for R. echinobothrida, R. tetragona, and R. cesticillus, respectively. The sensitivity test demonstrated that R. echinobothrida and R. cesticillus-specific primers detect a minimum of 5×10−2 ng DNA, while R. tetragona-specific primers detect a minimum of 0.5 ng genomic DNA. The specific primers successfully developed in this study might be useful for detecting cysticercoids in intermediate hosts or adult stages in poultry for epidemiological surveys, management and control of infection. RESEARCH HIGHLIGHTS This study established specific primers for Raillietina species detection. The ITS2 region is an effective molecular marker for Raillietina identification. © 2021 Houghton Trust Ltd.