title: Environmental determinants correlated to Vibrio harveyi-mediated death of marine gastropods.
abstract: Vibrio harveyi is an emerging pathogen that causes mass mortality in a wide variety of marine animal species; however, it is still unclear which environmental determinants correlate V. harveyi dynamics and the bacterium-mediated death of marine animal life. We conducted a correlation analysis over a 5-year period (2003-2007) analysing the following data: V. harveyi abundance, marine animal mortality and environmental variables (seawater temperature, salinity, pH, chlorophyll a, rainfall and total viable bacterial counts). The samples were collected from a coastal area in northern Japan, where deaths of a marine gastropod species (Haliotis discus hannai) have been reported. Our analysis revealed significant positive correlations between average seawater temperature and average V. harveyi abundance (R = 0.955; P < 0.05), and between average seawater temperature and V. harveyi-mediated abalone death (R = 0.931; P < 0.05). Based on the regression model, n degrees C rise in seawater temperature gave rise to a 21(n)-fold increase in the risk of mortality caused by V. harveyi infection. This is the first report providing evidence of the strong positive correlation between seawater temperature and V. harveyi-mediated death of marine species.
authors.affiliation: Laboratories of Microbiology and Marine Bioresource and Environment Sensing, Faculty of Fisheries Sciences, Hokkaido University, 3-1-1 Minato-cho, Hakodate 041-8611, Hokkaido, Japan.
authors.forename: Youhei
authors.initials: Y
authors.lastname: Fukui
authors.forename: Sei-Ichi
authors.initials: S
authors.lastname: Saitoh
authors.forename: Tomoo
authors.initials: T
authors.lastname: Sawabe
mesh_terms: D000818:Animals; D002734:Chlorophyll / Q000032:analysis; D000077194:Chlorophyll A; D015169:Colony Count, Microbial; D004269:DNA, Bacterial / Q000235:genetics; D017753:Ecosystem; D004784:Environmental Monitoring; D049851:Gastropoda / Q000382:microbiology*; D006863:Hydrogen-Ion Concentration; D007564:Japan; D012623:Seawater / Q000032:analysis / Q000382:microbiology; D013696:Temperature; D014733:Vibrio / Q000235:genetics / Q000254:growth & development*; D014735:Vibrio Infections / Q000382:microbiology*; D014871:Water Microbiology
chemical_list: D004269:DNA, Bacterial; D002734:Chlorophyll; D000077194:Chlorophyll A