Jembrana disease virus (JDV) is a viral pathogen that causes Jembrana disease in Bali cattle (Bos javanicus) with high mortality rate. An easy and rapid diagnostic method is essential for further control this disease. We used a reverse transcription loop-mediated isothermal amplification (RT-LAMP) combined with lateral flow dipstick (LFD), based on conserved tm subunit of Jembrana disease virus env gene. The RT-LAMP conditions were optimized by varying the concentration of MgSO 4 , betaine, dNTP, and temperature as well as the time and duration of reaction. The primers sensitivity for JDV was confirmed. The method was able to detect env-tm gene dilution which contained 2 9 10 -15 g of template. Comparatively, the sensitivity of RT-LAMP/LFD was 100-fold more sensitive than reverse transcription-polymerase chain reaction. The primers specificity for JDV was also confirmed using positive and negative controls. This work also showed that virus detection could be done not only on total RNA extracted from blood but various organs could also be analyzed for the presence of JDV using RT-LAMP/LFD method. The whole process, including the LAMP reaction and the LFD hybridization step only lasts approximately 75 min. Results of analysis can be easily observed with naked eyes without addition of any chemical or further analysis. The combination of RT-LAMP with LFD makes the method a more suitable diagnostic tool in conditions where sophisticated and expensive equipments are not available for field investigations on Jembrana disease in Bali cattle.

Jembrana disease virus is a viral pathogen that causes Jembrana disease in Bali cattle (Bos javanicus) with high mortality rate. Infection of Jembrana Disease Virus (JDV) on Bali cattle have caused substantial economic losses for farmers in Indonesia and Australia. In order to control the spread, development of a sensitive detection method is important. In this study, we used three different detection methods based on genomic approach, i.e., reverse transcriptase-polymerase chain reaction (RT-PCR), reverse transcriptase-loop mediated isothermal amplification (RT-LAMP) and dot-blot hybridization to detect JDV. Utilization of pGEX-TM, a recombinant plasmid containing env-tm gene as a positive control showed that RT-LAMP is the most sensitive method compares the two others. It could detect template concentration as low as 10 −6 ng µL −1 or equivalent to 1.52×10 2 plasmid copy number, 100 and 10000 more sensitive than RT-PCR and dot-blot hybridization, respectively.