In the research reported here, the pathology, virulence, and strain differences of Taura syndrome virus (TSV) was studied. Initial studies on TSV pathogenesis compared the survival of juveniles of a highly Taura syndrome (TS) susceptible line of Penaeus vannamei, a line of TS resistant P. vannamei, and an innately TS resistant P. stylirostris line following TSV challenge by feeding (per os) or injection methods, in the absence of horizontal transmission via cannibalism and/or absorption from the water. Per os_TSV challenge resulted in I00% survival in P. stylirostris, but challenge by per os exposure produced significant mortality commencing on about the same post-exposure day in both SPF and SPR P. vannamei (P < 0.001), suggesting that P. stylirostris is significantly (P < 0.001) more resistant toper os TSV infection and presentation of TS disease than either SPF or SPR P. vannamei. The potential roles of the cuticular lining of the stomach and hindgut and unlined portions of the gut in TSV resistance in penaeid shrimp are discussed as factors where an innate resistance mechanism was postulated to explain the observed differences between the different species and populations of shrimp in TSV susceptibility. To investigate apparent TSV strain differences, three geographic and year isolates of TSV from naturally occurring TS epizootics of cultured penaeid shrimp were obtained from Mexico (SIN98TSV and MX99TSV from P. vannamei and SON2KTSV from P. stylirostris) and one TSV isolate from Belize, Central America (BLZ02TSV from P. vannamei) were analyzed and compared to the reference TSV isolate (HI94TSV) by selected TSV diagnostic and genetic analysis methods. The results show that screening of penaeid shrimp broodstock and postlarvae by MAb I Al testing will not detect all TSV isolates, possibly leading to false negative results, further spread of TSV and re-emergence of TS in regions where it has been eradicated. The putative VP1 antigenic epitope recognized by TSV MAb 1A1 is identified, with SIN98TSV and BLZ02TSV having 70.0% and 80.0% AA homology, respectively, within the 10 AA region. There are three distinct electropherotypes and 'serotypes' of TSV, with electropherotype A (TSV Etype-A) and serotype A (TSV-A) representing those TSV isolates conforming to VP1 properties of the Hawaiian 1994 TSV isolate, electropherotype B (TSV Etype-B) and serotype B (TSV-B) representing those TSV isolates conforming to the VP1 properties of the Sinaloan 1998 TSV isolate, and electropherotype C (TSV Etype-C) and TSV serotype C (TSV-C), representing those TSV isolates conforming to the VP1 properties of the Belize 2002 TSV isolate. In a parallel activity, the University of Arizona (UAZ) Aquaculture Pathology Diagnostic Laboratory (APL) Case Database (DB) and the UAZ Aquaculture Pathology Diagnostic Laboratory Client Address Book Database (AB), relational databases, were created using FileMaker Pro software, are used to keep an up to date and accurate record of all UAZAPL diagnostic and research case and client information and may be searched and sorted to find case data and/or client information of interest.
| Identifer | oai:union.ndltd.org:arizona.edu/oai:arizona.openrepository.com:10150/280124 |
| Date | January 2002 |
| Creators | Erickson, Heidi S. |
| Contributors | Lightner, Donald V. |
| Publisher | The University of Arizona. |
| Source Sets | University of Arizona |
| Language | en_US |
| Detected Language | English |
| Type | text, Dissertation-Reproduction (electronic) |
| Rights | Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. |
Page generated in 0.0105 seconds