Abstract: Blood serum parameters from Chinese sturgeons (Acipenser sinensis) were examined during a 27 day gradual acclimation period from seawater (26.7 salinity) to slightly brackish water (2.5‰) and subsequent transfer to freshwater (0‰ salinity) for a further 30 day period. The results were compared against serum samples from a control group reared throughout in freshwater. For each fish, the levels of 24 serum biochemical parameters were examined. The results indicated that gradual transfer from seawater to brackish water caused the serum concentrations for potassium, sodium, and calcium ions to decrease. This trend was also observed for blood urea-nitrogen (BUN), inosine(CR), uric acid(UA), alanine aminotransferase(ALT), gamma glutamyl transpeptidase (GGT), and total bile acid (TBA). All other serum parameters showed only transient changes or no changes at all. After being held subsequently for 30 days in freshwater, the four ion concentrations returned to values considered normal for seawater, indicating that Chinese sturgeon are capable of homeostasis.However, the other six parameters did not return to initial values. In fact, ALP, ALT and Fe2+ levels were raised in comparison to the freshwater control group. These observations indicate that major physiological changes occur during the acclimation process. Specifically, at 21‰ salinity a number of biochemical parameters were subject to noticeable fluctuations,suggesting this level may represent the pivotal condition of physiological regulation. Hence, it may be energetically costly for osmoregulatory processes to return to normal in Chinese sturgeon, due to metabolic and nutrient related functions taking much longer to recover.


附件下載：X.Y.Zhang, Q.W.Wei, X.F.Zhang, et al. Changes in serum biochemical parameters of Acipenser sinensis, Gray 1835, caused by decreasing environmental salinity. J.Appl.Ichthyol. 2011,27: 235-240. pdf