PHYSIOLOGICAL RESPONSES OF BROWN CRAB (CANCER PAGURUS LINNAEUS 1758) TO DRY STORAGE UNDER CONDITIONS SIMULATING VITALITY STRESSORS

Knowledge of the brown crab's (Cancer pagurus Linnaeus 1758) tolerance to emersion related to air temperatures and duration is scarce. In the current study, the condition of the brown crab was examined during emersion in laboratory experiments simulating dry storage and transport at air temperatures between 2-20 degrees C. Samples of hemolymph were taken at different intervals simultaneously as the crab was classified using a vitality index based on behavior and responses. Individual variances in hemolymph pH, total ammonia (TA), lactate, and glucose were large; but, in general, pH decreased and TA and lactate increased during emersion, most at the highest temperatures. When hemolymph samples were grouped according to vitality index, deterioration was found for pH, TA, and lactate as the vitality dropped, whereas no trend was found for glucose. Vitality of crabs was reduced during emersion, with the greatest reduction being crabs exposed to high temperatures. To secure strong and healthy crabs, exposure at 20 degrees C and 15 degrees C should not exceed 5 h and 10 h, respectively. For crabs exposed at 10 C and 5 degrees C, emersion for 36 h and 72 h, respectively, did not seem to have negative consequences for the animals. A general increase in vitality occurred when crabs were reimmersed. Delayed mortality occurred for weak and moribund crabs, highest during the first 24 h of reimmersion, and continuing over the next day, suggesting that such crabs should not be transported in the live value chain.