Evidence of decapods with DIV1-ATPase PCR positive, but no pathognomonic lesions of DIV1 infection
Issued Date
2025-06-30
Resource Type
ISSN
00448486
Scopus ID
2-s2.0-105000784499
Journal Title
Aquaculture
Volume
604
Rights Holder(s)
SCOPUS
Bibliographic Citation
Aquaculture Vol.604 (2025)
Suggested Citation
Srisala J., Jitchana S., Suebsing R., Sanguanrut P., Thawonsuwan J., Thaiue D., Guo X., Flegel T.W., Sritunyalucksana K., Chuchird N., Prachumwat A. Evidence of decapods with DIV1-ATPase PCR positive, but no pathognomonic lesions of DIV1 infection. Aquaculture Vol.604 (2025). doi:10.1016/j.aquaculture.2025.742449 Retrieved from: https://repository.li.mahidol.ac.th/handle/123456789/108541
Title
Evidence of decapods with DIV1-ATPase PCR positive, but no pathognomonic lesions of DIV1 infection
Author's Affiliation
Corresponding Author(s)
Other Contributor(s)
Abstract
Decapod iridescent virus 1 (DIV1) is an emerging pathogen of farmed crustaceans. Using the same DIV1-ATPase target gene for PCR detection as recommended by the World Organization for Animal Health (WOAH) in our Thailand surveillance program, we found 66.0 % and 98.5 %, respectively, of the whiteleg shrimp Penaeus vannamei and giant river prawn Macrobrachium rosenbergii to be ATPase-PCR positive but showing grossly normal without signs of disease in successful cultivation crops of several regional farms. Although having identical ATPase PCR target sequences to that of the pathogenic DIV1, these ATPase-PCR-positive healthy decapods had no pathognomonic DIV1 lesions. In addition, there was no in situ hybridization (ISH) signals of DIV1 in the cytoplasm of the cells in the target tissues such as hematopoietic tissue (HPT) and gills, but ISH signals were found in nuclei of the gill and the hepatopancreas (HP) tubule epithelium cells instead. Subsequently, a comparative bioassay was performed using either purified viral inoculums from healthy (ATPase-HS or ATPase-HP) or diseased (ATPase-DS or ATPase-DP) P. vannamei and M. rosenbergii to be intramuscularly injected into naïve animals. While the group injected with the purified viral inoculum of diseased decapods showed the mortality of 100 % (5/5) and 40 % (2/5) for P. vannamei and M. rosenbergii within 5 days post injection, the groups injected with inoculums prepared from healthy ones had no mortality, no disease signs, no histological lesions, no viral replications and without observed viral particles. Transmission electron microscopy revealed the DIV1 virions in the inoculum prepared from ATPase-DS and ATPase-DP, but not in ATPase-HS or ATPase-HP. Analysis of the total ∼ 27 million shotgun metagenomic sequencing reads from the DNA extracted from the crude inoculum of healthy P. vannamei (ATPase-HS) recovered only 602 mappable sequencing reads distributed over some regions of the DIV1 genome sequence including the ATPase PCR target region but without an intact, complete DIV1 genomic sequence. Altogether, these results suggest an existence of DIV1 viral inserts in decapod genomes as endogenous viral elements (EVE) in both P. vannamei and M. rosenbergii. There is some urgency to revise the DIV1 detection methods to prevent trade restrictions arising from false-positive PCR test results for DIV1.