Taura Syndrome Virus (TSV) was first reported in the Gulf of Guayaquil, Ecuador in 1992 and has caused severe impact on the L. vannamei culture industry since then. This virus is widely seen in America as well as Asia, particularly in Taiwan and China as a result of improper introduction of L. vannamei brood stocks in the late 1990s. The disease phases of this positive sense, single strained picornavirus, could be classified into 3 stages. In the acute phase, the diseased animals show a red discolouration in the tail and appendages and usually die whilst molting. The mortality rate is estimated at 80% to 85%. Shrimps that survive the molting process come to the recovery phase or the chronic phase. In the chronic phase, infected shrimps appear and behave normally despite remain diseased.

By comparing the nucleotide sequences of the viruses collected from Latin America and Asia, a conserved region was found within the capsid protein encoding area, and the sequence homology is over 98% within the collected samples. IQ2000™ TSV Detection and Prevention System is designed on the basis of this specific sequence. Similar to other IQ2000™ serial products, the internal control and semi-quantitative design are also included to eliminate the false negative possibility. While designing this system, the potential cross reaction with other insect picornaviruses was focally considered and avoided. This System also passed the cross-reaction tests with the other major shrimp viruses, such as WSSV, IHHNV, YHV, GAV, MBV, and BP.

￭ Packing size: 200 reactions.

￭ Detection Limit: 10 copies/reaction.

￭ Quantitative capability: 4 different levels of infection can be differentiated.

￭ Sample throughput: for 40 samples, from sample preparation to final results require 4.5 to 5 hours.

￭ Built-in internal control system: eliminate false negative results from failed extraction or reaction.

￭ Quantified positive standard: monitor the sensitivity of detection.

￭ Adaptable to the Uni-IQ RT-PCR profile, suitable for multi-viral diagnosis.

Lane 1: TSV P(+) standard, 2,000 copies/reaction

Lane 2: TSV P(+) standard, 200 copies/reaction

Lane 3: TSV P(+) standard, 20 copies/reaction

Lane 4: Negative control (Yeast tRNA or ddH₂O)

Lane 5: Sample of severe TSV infection

Lane 6: Sample of moderate TSV infection

Lane 7: Sample of light TSV infection

Lane 8: Sample of very light TSV infection

Lane 9: TSV negative sample

Lane M: Molecular weight markers, 848 bp, 630 bp, 333 bp

￭This reagent is intended for testing fresh, frozen, and ethanol-preserved samples, e.g. gill and PL.

￭Ideal for the specific pathogen-free (SPF) animal selection, evaluation of culture environment, grow-out monitoring, and quarantine service.