ISSN:
1365-2109
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Some metabolic end-products in tissues and physiological parameters of haemolymph of the Japanese clam Ruditapes philippinarum (Adams & Reeve) were investigated under aerial exposure at 15 °C with low relative humidity (RH) (22%) or high RH (91%). Acclimated clams in water at 15 °C were used as a control and to supply the low or high RH experiment. The low RH experiment was conducted at air exposure for 50 h (LH50), and the high RH experiment for 50 h (HH50) and 100 h (HH100). Accumulation of succinate and alanine in the tissues proved that the clam shifted its metabolism to anaerobiosis. Lactate accumulation did not occur. Glucose concentrations in tissues increased slightly during exposure except for HH50. The total free amino acid contents (363–410 μmol g−1) were higher than those of glucose (530–804 μmol 100 g−1), suggesting that the free amino acids might play a more dominant role in the metabolism. Increase in the haemolymph pco2 did not influence the acid–base balance in the haemolymph during exposure at both humidity conditions. Increase in the haemolymph ammonia from 48.2 to 57.1 μmol 100 g−1 and to 131.0 μmol 100 g−1 at LH50 and HH100, respectively, suggested that ammonia might function as an important buffering factor during aerial exposure. Retention values of the haemolymph po2 even at the longest exposure time (16.30 mmHg at LH50 and 14.69 mmHg at HH100) indicated that the clams depend partially on some aerobic manner.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1046/j.1365-2109.2000.00402.x
