Interactive effects of elevated temperature and Photobacterium swingsii infection on the survival and immune response of marine mussels (Perna canaliculus): A summer mortality scenario

• DOI: 10.1016/j.marenvres.2024.106392
• Publication Date: 2024-02-03T16:13:48Z
• Authors: Awanis Azizan; Leonie Venter; Jingjing Zhang; Tim Young; Jessica A. Ericson; Natalí J. Delorme; Norman L.C. Ragg; Andrea C. Alfaro
• Keywords: 2 Aetiology; 570; Bacteria; 34 Chemical Sciences; Photobacterium; 05 Environmental Sciences; Temperature; 3 Good Health and Well Being; Biomarker; Multiple stresses; 41 Environmental Sciences; 06 Biological Sciences; 14 Life Below Water; Marine Biology & Hydrobiology; Vaccine Related; Perna canaliculus; Summer mortality; Infectious Diseases; Emerging Infectious Diseases; 2.2 Factors relating to the physical environment; Greenshell™ mussel; Immune response; Infection; 03 Chemical Sciences; 31 Biological Sciences

The New Zealand Greenshell™ mussel (Perna canaliculus) is an economically important aquaculture species. Prolonged increases in seawater temperature above thermotolerance ranges pose a significant threat to survival and health, potentially increasing susceptibility bacterial infections. Using challenge experiments, this study examined the combined effects of increased (Photobacterium swingsii) infection on animal survival, haemocyte biochemical responses adult mussels. Mussels maintained at three temperatures (16, 20 24 °C) for seven days were either not injected (control), with sterile marine broth (injection control) or P. swingsii (challenged medium high doses) monitored daily five days. Haemolymph tissue samples collected 24, 48, 72, 96, 120 h post-challenge analysed quantify colonies, responses. infected exhibited mortalities °C, likely due compromised immune system, but no observed when was only stressor. Bacterial colony counts haemolymph decreased over time, suggesting clearance followed by activation signalling pathways. Total viability data supports defence functions being stimulated presence pathogen loads °C. In gill tissue, oxidative stress responses, measured as total antioxidant capacity malondialdehyde (MDA) levels, higher mussels (compared controls) after 24h 120h lowest (16 highest (24 °C), indicating stressors. Overall, work confirms that Photobacterium pathogenic canaliculus indicates may be more vulnerable pathogens under conditions elevated temperature, such those predicted future climate change scenarios.