1. Effects of chronic hypercapnia and elevated temperature on the immune response of the spiny lobster, Jasus lalandii
- Author
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B.M. Macey, Lutz Auerswald, Jarred L. Knapp, and Louwrens C. Hoffman
- Subjects
0301 basic medicine ,Vibrio anguillarum ,Hot Temperature ,animal structures ,Zoology ,Aquatic Science ,pCO2 ,03 medical and health sciences ,Jasus lalandii ,Hemolymph ,medicine ,Animals ,Environmental Chemistry ,Seawater ,Palinuridae ,biology ,Ocean acidification ,04 agricultural and veterinary sciences ,General Medicine ,Carbon Dioxide ,Hydrogen-Ion Concentration ,biology.organism_classification ,Crustacean ,Immunity, Innate ,030104 developmental biology ,040102 fisheries ,0401 agriculture, forestry, and fisheries ,medicine.symptom ,Hypercapnia ,Spiny lobster - Abstract
The West Coast rock lobster (WCRL), Jasus lalandii, inhabits highly variable environments frequented by upwelling events, episodes of hypercapnia and large temperature variations. Coupled with the predicted threat of ocean acidification and temperature change for the coming centuries, the immune response in this crustacean will most likely be affected. We therefore tested the hypothesis that chronic exposure to hypercapnia and elevated seawater temperature will alter immune function of the WCRL. The chronic effects of four combinations of two stressors (seawater pCO2 and temperature) on the total number of circulating haemocytes (THC) as well as on the lobsters’ ability to clear (inactivate) an injected dose of Vibrio anguillarum from haemolymph circulation were assessed. Juvenile lobsters were held in normocapnic (pH 8.01) or hypercapnic (pH 7.34) conditions at two temperatures (15.6 and 18.9 °C) for 48 weeks (n = 30 lobster per treatment), after which a subsample of lobsters (n = 8/treatment), all at a similar moult stage, were selected from each treatment for the immune challenge. Baseline levels of haemocytes (THC ml−1) and bacteria (CFU ml−1) in their haemolymph were quantified 24 h prior to bacterial challenge. Lobsters were then challenged by injecting 4 × 104 V. anguillarum per g body weight directly into the cardiac region of each lobster and circulating haemocyte and culturable bacteria were measured at 20 min post challenge. No significant differences in THC ml−1 (p normocapnia/high temperature > normocapnia/low temperature > hypercapnia/high temperature. This study demonstrated that despite chronic exposure to combinations of reduced seawater pH and high temperature, the WCRL was still capable of rapidly rendering an injected dose of bacteria non-culturable.
- Published
- 2019