Temperature modulate disease susceptibility of the Pacific oyster Crassostrea gigas and virulence of the Ostreid herpesvirus type 1
|Author(s)||Delisle Lizenn1, Petton Bruno2, Burguin Jean Francois1, Morga Benjamin3, Corporeau Charlotte1, Pernet Fabrice1|
|Affiliation(s)||1 : IFREMER, LEMAR, UMR 6539, Technopole Brest Iroise, F-29280 Plouzane, France.
2 : IFREMER, LEMAR, UMR 6539, F-29840 Presquile Du Vivier, Argenton, France.
3 : IFREMER, LGPMM, Ave Mus Loup, F-17390 La Tremblade, France.
|Source||Fish & Shellfish Immunology (1050-4648) (Academic Press Ltd- Elsevier Science Ltd), 2018-09 , Vol. 80 , P. 71-79|
|WOS© Times Cited||13|
|Keyword(s)||Bivalve, Health, Marine disease, Mortality risk, Temperature, Virulence|
Temperature triggers marine diseases by changing host susceptibility and pathogen virulence. Oyster mortalities associated with the Ostreid herpesvirus type 1 (OsHV-1) have occurred seasonally in Europe when the seawater temperature range reaches 16–24 °C. Here we assess how temperature modulates oyster susceptibility to OsHV-1 and pathogen virulence. Oysters were injected with OsHV-1 suspension incubated at 21 °C, 26 °C and 29 °C and were placed in cohabitation with healthy oysters (recipients) at these three temperatures according to a fractional factorial design. Survival was followed for 14 d and recipients were sampled for OsHV-1 DNA quantification and viral gene expression. The oysters were all subsequently placed at 21 °C to evaluate the potential for virus reactivation, before being transferred to oyster farms to evaluate their long-term susceptibility to the disease. Survival of recipients at 29 °C (86%) was higher than at 21 °C (52%) and 26 °C (43%). High temperature (29 °C) decreased the susceptibility of oysters to OsHV-1 without altering virus infectivity and virulence. At 26 °C, the virulence of OsHV-1 was enhanced. Differences in survival persisted when the recipients were all placed at 21 °C, suggesting that OsHV-1 did not reactivate. Additional oyster mortality followed the field transfer, but the overall survival of oysters infected at 29 °C remained higher.