Main content area

Responses of metabolism and haemolymph ions of swimming crab Portunus trituberculatus to thermal stresses: a comparative study between air and water

Lu, Yunliang, Wang, Fang, Li, Li, Dong, Shuanglin
Aquaculture research 2016 v.47 no.9 pp. 2989-3000
Portunus trituberculatus, air, anaerobiosis, calcium, crabs, glucose, glycogen, hemolymph, hepatopancreas, ions, lactic acid, lipids, magnesium, metabolites, physiological response, potassium, sodium, temperature, urea
Two approaches (i.e. water and dry or semi‐dry transport) have been developed for the transport of swimming crabs Portunus trituberculatus in recent years. To evaluate their differential effects on physiological responses of crabs, we measured haemolymph components (metabolic substrates, metabolites and ions) and hepatopancreas glycogen level at different time intervals after exposure of crabs to thermal stresses in water and air. The immersed crabs exhibited no significant change in all metabolic substrates except the glucose level in the hypothermal stressed treatment (P > 0.05), whereas there was a great variation in haemolymph glucose and lipid level of air exposed crabs under both thermal stresses (P < 0.05). With respect to metabolites in immersed crabs, only urea concentration in hypothermal stressed crabs and lactate concentration in hyperthermal stressed crabs changed significantly during the experiment; by contrast, the air exposed crabs responded significantly in all metabolites to thermal stresses (P < 0.05). The immersed crabs decreased the concentration of Na⁺ and Mg²⁺, but increased the concentration of K⁺ and Ca²⁺. The change in Na⁺ and Ca²⁺ were not significant in the hyperthermal stressed crabs (P > 0.05). Nevertheless, all ions except K⁺ accumulated significantly in the air exposed crabs after thermal stresses (P < 0.05). Crabs in the two different media responded similar to thermal stresses in metabolism but differed greatly in ions regulation. The effects of thermal stresses on crabs could be magnified by exposure to air, leading to animals relying more on anaerobic metabolism and therefore limiting the usage of dry or semi‐dry transport approach especially at high temperature.