جستجوی مقالات مرتبط با کلیدواژه « amino acid » در نشریات گروه « محیط زیست »

Olfaction is one of the fundamental senses to detect odors from long distances in sturgeons, and it plays an important role in feeding behavior and orientation fish. This sense can be a reliable criteria to investigate the effect of pollutants on aquatic organisms. Therefore, the main objective of this study was to evaluate effects of silver nanoparticles on olfactory feeding behavior of Persian sturgeon. This behavior was investigated following exposure to 0.01, 0.005 and 0.001 mg L-1 AgNPs for 7 days (each group with 3 replicates) and 6 amino acids were used to evaluate the olfactory behavior. During the course of the experiment, solution containing amino acids was introduced into the aquarium for 3 min. Then the number of fish and their behavior was counted every30 sec after the start of each trial. The results showed that the concentration of 0.01 mg L-1 AgNPs significantly reduced the olfactory attractiveness of alanine, glycine and leucine amino acids. Also, olfactory behavior responses were significantly reduced only at a concentration of 0.01 mg / L. but responses to the repellant amino acids (tyrosine, aspartic acid and glutamic acid) were not significantly different in none of the concentrations of silver nanoparticles.

Arginine is one of the amino acids that its impact on improving the growth and immune system of human and many animals always been one of interest of researchers. In this study, the effect of this amino acid on growth indices and resistance against salinity tension on common carp fish has been investigated. For this purpose, four treatments (each treatment with three replicates) were made from common carp and fed with dietary foods containing arginine 0, 1.5, 2 and 2.5% for 60 days. During this period, the fishes three times were biometrics. Data analysis was performed using SPSS software version 18 and Excel and the comparing the mean of treatments in a completely randomized design have been performed analysis with Duncan test and one way ANOVA and existent or lack significant difference were performed in 5% of the level Probability (P<0.05). Regarding to the results obtain from arginine acid on food conversion rate (FCR), body weight gain and percentage of body weight gain of carp, it had significant impact (P <0.05), however, increasing body weight gain and decreasing FCR were observed in treatment groups (P<0.05), however condition factor (CF), growth specific rate (SGR) and survival rate (SR), did not showed any significant difference (P>0.05). Therefore, according to the present results, applying of salinity stress on different treatments showed that the presence of arginine in the feed of carp fish may have a significant effect on their resistance and survival, so that for feed treatments with 1.5% and 2% of arginine within 72 hours did not show any casualties, therefore. Hence, according to the present results, use of 2% L-Arginine to increase weight of carp, recommended.