نشریه پژوهش های علوم و فنون دریایی
سال دهم شماره 1 (بهار 1394)

The main objective of this research was to study the effects of diets containing 1, 2, 3 and 4 percent pomegranate peel meal and also the control diet with no pomegranate peel meal, on the changes in carotenoid levels of fillet, blood and skin color of rainbow trout (Oncorhynchus mykiss). The experiment had a completely randomized design with four treatments, one control group and 3 replicates. Four hundred and fifty rainbow trout fish with a mean weight of 45 ± 5 g were divided into 15 small concrete canals. During a period of 60 days pomegranate peel meal was added to the fish diet, which had a significant effect on the carotenoid levels of fillet, blood and skin (P≤0.05) and subsequently the production of red color. Skin and fillet carotenoid concentrations were highest in treatments 1 and 3 with 1 and 3 percent added pomegranate peel meal (P≤0.05). Addition of 1 and 3 percent pomegranate peel meal had the best coloration in (3.33±0.01 & 3.28±0.07 mg/kg) fillet and skin respectively. The results showed that the blood carotenoids levels in treatments of 1 and 3 percent, were significantly higher than other treatments (P<0.05) and the lowest level (0/34±0/01 mg/l) was found in the control group.

In this research, the Halodule uninervis sea grass was collected in the tidal area of Golshahr (Bandarabaas-Iran) in maximum period of ebb in summer-autumn- winter 88 to spring 89. The physiological analysis of Halodule uninervis was performed three times by measuring Photosynthetic pigments (Chlorophylls a, b and Carotenoids) and the amount of Prolinewas also investigated. The results indicated that the minimum amount of Chlorophyll a was found in spring (1/19 ± 0/002 mg/g) and the minimum amount of Chlorophyll b (0/68 ± 0/003 and 0.68 ± 0/003 mg/g) and Carotenoids (1/25 ± 0/002 and 1/26 ± 0.002 mg/g) was found in autumn and winter respectively. The Proline measurement revealed that the amount of Proline in roots was less in comparison to the leaves and the minimum amount of Proline found in roots was in spring (0/07 ±0/006 mg/g) and summer ( 0/08 ± 0.004 mg/g).

Azolla filiculoides Lam. a small aquatic and planktonic fern, is found floating on the surface of canals, lakes, wetlands and ponds. Azolla can be used as a bio-filter in the entrance pathway of industrial waste materials to wetlands and rivers, to absorb and remove heavy metals. This research was done in the summer (hot season) and the winter (cold season) of 2011-2012, in three stations Pesikhan (Eastern region), Siah Darvishan (Central region) and Siah Kashim and Abkenr (Western region), in Anzali lagoon. Roots and leaves of sampled Azolla were separated and after digestion, the concentration of chromium and zinc, in mg/kg of the dry weight, was measured using electrothermal atomic absorption. Results showed that the concentrations of zinc and chromium in the east of Anzali Lagoon were higher than the west and central regions. Average concentrations of zinc and chromium in the eastern section of the lagoon were (62/84 ±3/13, 3/14 ± 1/07), in the west (27/64 ±22/03, 1/3 ± 1/1) and in the center (29/97 ±23/3, 2/33 ±1/8) ppm, respectively. The highest contamination was noticed in the eastern area, then central, and finally in the western region of Anzali Lagoon. Results showed that in all regions of Anzali Lagoon, concentration of Cr and Zn were significantly higher in roots in comparison to leaves of Azolla (P<0.05). Also, in summer there were higher levels of heavy metals in roots and leaves than in winter. In present research, there were a positive correlation between concentration of heavy metals and temperature, but there was no correlation with other parameters. According to the results, the mean concentration ​​ of chromium (2.25 ppm) in Azolla was significantly higher than the permissible limit of chromium for plants (1.30mg/kg), recommended by WHO, while zinc (40.15 ppm) was lower than WHO’s recommended limit for zinc in plants (50 mg/kg).

Enrichment of live-food for aquatics, to enhance their nutritional value, is essential for fish aquaculture. Accordingly, various commercial suspensions are prepared and are available in the world. These suspensions are widely used in Iranian aquaculture. In this study, in order to prepare similar suspensions in the Research Institute, analysis of foreign suspension was done. In this study Artemia nauplii were used as the representative live-food. Shark liver oil and extraction of sunflower oil and other substances were also used. Suspensions were compared with the control sample via various tests. Live foods were enriched with fatty acids in the suspensions as defined according to standard procedures. The results showed that the enriching percent of these suspensions in control nauplii and research center enriched nauplii were 3±37 and 25 ± 3, respectively. Then the influence of live enriched Artemia nauplii on 500 new feed trout larvae in 4 treatments were experimented for a 30 days period, to evaluate the biometric factors. The results showed that treatments 1 and 2 significantly differed compared with the treatments 3 and 4 in survival, growth rate, the total length and the abnormalities. However, no significant difference was observed between treatment 3 and 4 together. Final research results suggest that the prepared suspension containing essential fatty acids similar to foreign samples was successful in all field trials.

In the present study macroinvertebrate community of Jajrood River branches was studied. Sampling from branches of Abnik, Zayegan, Lalan and Ahar was conducted in spring and summer of 1393. Benthic invertebrate were collected by Surber sampler (35 × 35 cm) and fixed in 10% formalin. Benthos samples were separated in the laboratory by lifting loop and were identified at genus level. To assess the ecological condition and water quality Hilsenhoff and EPT indices were used. In general, 28 genus and 3 phyla, 5 classes, 9 orders and 24 families were identified in macroinvertebrate community of these rivers. The highest density of benthos was seen in Lalan branch (842 per square meter), in spring and summer. Among the genera found in all branches, except in Ahaar branch, maximum density was seen for Epeorus genus in summer and Baetis genus in spring. Based on analysis of variance (ANOVA) and post hoc LSD test, significnat difference was only seen when benthos population of Ahaar was compared with the other branches (P <0.05).

Blood parameters are often used as indicator for stress and health condition evaluation in fishes. The aim of this study was to compare blood and biochemical indices between stellate sturgeon (Acipenser stellatus) and Common Carp (Cyprinus carpio). In total, 20 brood stock fish (including 10 of each species) were selected and their blood samples were taken. Results showed that the mean counts of red blood cells (RBC), white blood cells (WBC), percentage of haematocrit (Hct), level of hemoglobin (Hb), cholesterol and osmolarity in Common Carp was more than Stellate sturgeon, although no significant difference was observed(P≥0.05). Differential count of leucocytes showed that the mean lymphocyte percentage in A.stellatus was more than C.carpio, while there was no significant difference seen in percentage of neutrophiles, Eosynophiles and monocytes in C.carpio compared with A.stellatus (P≥0.05). Mean level of Glucose in C.carpio was significantly more than A.stellatus (P≤0.05). On the other hand, mean level of triglyceride, albumin and total protein in A.stellatus was significantly more than C.carpio (P≤0.05). Cytomorphological parameters of RBC such as cell area, nucleus area and MCV in A.stellatus was significantly more than C.carpio. Therefore, the levels of some blood parameters were different in stellate sturgeons (Acipenser stellatus) in comparison with Common Carp (Cyprinus carpio), that can be related to their development differences.

Blood parameters are often used as indicator for stress and health condition evaluation in fishes. The aim of this study was to compare blood and biochemical indices between stellate sturgeon (Acipenser stellatus) and Common Carp (Cyprinus carpio). In total, 20 brood stock fish (including 10 of each species) were selected and their blood samples were taken. Results showed that the mean counts of red blood cells (RBC), white blood cells (WBC), percentage of haematocrit (Hct), level of hemoglobin (Hb), cholesterol and osmolarity in Common Carp was more than Stellate sturgeon, although no significant difference was observed(P≥0.05). Differential count of leucocytes showed that the mean lymphocyte percentage in A.stellatus was more than C.carpio, while there was no significant difference seen in percentage of neutrophiles, Eosynophiles and monocytes in C.carpio compared with A.stellatus (P≥0.05). Mean level of Glucose in C.carpio was significantly more than A.stellatus (P≤0.05). On the other hand, mean level of triglyceride, albumin and total protein in A.stellatus was significantly more than C.carpio (P≤0.05). Cytomorphological parameters of RBC such as cell area, nucleus area and MCV in A.stellatus was significantly more than C.carpio. Therefore, the levels of some blood parameters were different in stellate sturgeons (Acipenser stellatus) in comparison with Common Carp (Cyprinus carpio), that can be related to their development differences.

Synthetic man-made Persian Gulf Martyrs Lake in the North-West of Tehran, in the 22nd region, with a volume of 10 million cubic meters, an area of 224 hectares and an average depth of 10 meters, is the largest man-made lake in Iran. In this study to assess the risks arising from the exploitation phase of Persian Gulf Martyrs Lake, multi-criteria decision making, MADM, was used. In this regard, the risks of exploitation using questionnaire, were also analyzed using SPSS software and TOPSIS method. For the risk factors and prioritization of the risks of the lake, Analytical Hierarchy Process (AHP) was used. In this method, for the hierarchical structure analysis of the risks of the lake, matrix pair comparison was performed using pairwise comparison of each of the criteria options and in relation to each other. Finally, to determine the probability of occurrence of each risk, Expert Choice software was used; also using FMEA logic, the results were assessed. Based on the results, it was found that in the physical & chemical environment, impact on ground water and sedimentation was the most important risk factor and eutrophication was identified as the most important biological risk.