No abstract

In order to investigate the effect of anesthesia on serum parameters, Beluga, Huso huso (L.) were blood-sampled immediately without anesthesia (control) or subjected to following anesthesia procedure: 40, 120, and 240 s exposure to 3,000, 700, and 500 mg l⁻¹ clove solution, respectively. Blood samples were collected after these periods, when fish were immobile and reached stage 4 anesthesia. Results showed that cortisol and glucose levels were significantly high in 700 and 500 but not 3,000 mg l⁻¹ group compared to control. Serum lactate levels were significantly high in 500 mg l⁻¹ group compared to control group. Lactate levels were not significantly differed between control, 3,000, and 700 mg l⁻¹ groups. There were no significant differences in serum levels of cholesterol, total protein, lactate dehydrogenase, aspartate aminotransferase, alanine aminotransferase, Na⁺, Cl⁻, K⁺, and Ca²⁺. Results suggest that rapid anesthesia with higher dose is better than slow anesthesia with lower dose for blood sampling in Beluga.

No abstract

Effect of dietary tryptophan (TRP) on copper toxicity was investigated in common carp, Cyprinus carpio. Fish were randomly distributed into two triplicate treatments (control and TRP) and fed control (TRP = 3.1 g kg(-1)) or TRP (TRP = 8.1 g kg(-1)) diets over a 2-week period. Then, both treatments were subjected to 10 mg l(-1) copper sulfate over a 7-day period. Mortality and serum cortisol, glucose, alanine aminotransferase (ALT), aspartate aminotransferase (AST), sodium, potassium, and chloride levels were recorded at 0, 24, 72, 120, and 168 h post-copper exposure. There was no mortality in the TRP group, whereas the control group mortality was started at 120 h post-copper exposure (21.7 ± 7.6 %) and reached 61.7 ± 10.4 % at the end of the experiment. Cortisol, glucose, ALT, and AST levels significantly (P < 0.05) increased after copper exposure in both groups; however, the control group showed significantly higher levels than the TRP group. In both groups, sodium decreased after copper exposure and did not return to the pre-exposure values. Potassium levels significantly increased 24 h post-copper exposure in both groups and remained significantly elevated in the control group at 72 h, when fell to the pre-exposure values in the TRP group. No significant changes were observed in the chloride levels in any groups. It is concluded that dietary TRP is capable to increase common carp tolerance to copper toxicity via mitigating copper-induced stress rather than restoring gill dysfunction and hydromineral imbalance.

Common carp juveniles were fed two types of diet (control: 0.1% tryptophan and TRP: 0.6% tryptophan) over 15 days. Thereafter, both groups were directly subjected to osmotic challenge (from 0 to 10 ppt) for 168 h. Blood samples were collected at -240, 0, 6, 24, 72 and 168 h after challenge. Survival and serum cortisol, glucose, sodium and chloride levels were measured to determine stress response and osmoregulation condition. While TRP group showed no mortality until 168 h, cumulative mortality was near 100% at 72 h after challenge in control group. Feeding tryptophan-supplemented diet led to increase in prechallenge cortisol, but not glucose, sodium and chloride values at -240 h that stayed elevated until 0 h after challenge. After challenge, cortisol and glucose values did not significantly affected by time of sampling but type of diet and diet×time interaction. Sodium values significantly affected by diet type and time of sampling but not their interaction. Chloride values significantly affected by time of sampling but not diet type and their interaction. Control group had higher cortisol, glucose and sodium than TRP at each time of sampling. Control and TRP group showed increasing and decreasing pattern in cortisol and glucose values when experiment progressed after osmotic challenge. Both group showed increasing pattern in sodium and chloride values when experiment progressed after osmotic challenge. Results indicated that tryptophan supplementation enhanced salt water tolerance of carp that is due to increase in basal cortisol and anti-stress effect of tryptophan and possibly increase in serotonergic activity.

We explore the effects of ultrafast shaped pulses for two-level systems that do not have a single-photon resonance, by developing a multiphoton density-matrix approach. We take advantage of the fact that the dynamics of the intermediate virtual states are absent within our laser pulse time scales. Under these conditions, the multiphoton results are similar to those for a single photon, and it is possible to extend the singlephoton coherent control ideas to develop multiphoton coherent control.

No abstract

A study was conducted to investigate the e¡ects of dietary citric acid (CA) (0,1%, 2% and 3%) on the calcium (Ca) and phosphorus (P) contents of muscle, scute and serum of Beluga (Huso huso) juveniles (25.1 AE 1.9 g). After 8 weeks of feeding on the experimental diets, the Ca and P contents of muscle, scute and serum were measured. The results revealed that the addition of 2% and 3% CA signi¢cantly increased the Ca and P contents of muscle and serum. Dietary CA had no e¡ect on the Ca content of scute, but the P content of scute was signi¢cantly higher compared with additional 1% CA and the control. These results indicate that the addition of CA to the diet of Beluga increased the bioavailability of Ca and P, thereby increasing muscle and scute mineralization.