Iranian Scientific Fisheries Journal
Year:2018 | Volume:27 | Issue:2 |Papers Count:23

In this research, the water quality of Gharehsou River within the fish farms in the 4 stations including the upstream station (as a control station), the station between farms, the station after the last farms and downstream after 4 km away from the last fish farm, was surveyed every 45 days from the December 2015 to May 2016. The purpose of this study was to investigate parameters including water temperature (˚ C), dissolved oxygen (DO), electrical conductivity (EC), pH, alkalinity, ammonia, nitrate, nitrite, TDS and TSS at the desired stations. The results showed that the highest and lowest levels of ammonia in stations between farms and downstream were found 0. 58 ± 0. 23 mg. l-1 and 0. 15 ± 0. 13 mg. l-1, respectively, which was significantly differed (p<0. 05). Also, nitrite level at station last farms was 0. 15± 0. 04 mg. l-1 significantly higher than other stations (p<0. 05). In terms of sampling time, the maximum mean ammonia and nitrate content were obtained in January and May, respectively. Minimum alkalinity, EC and nitrite were observed in June, which had a significant difference with other months (p<0. 05). Based on statistical analysis PCA (principal component analysis), temperature, dissolved oxygen and alkalinity showed the greatest positive impact and pH had most negative impact. Also with increasing temperature, ammonium nitrate was increased; but on the contrary, increase the nitric acid in water to be associated with reduced temperature. According to correlation station with the results, most of the examined factors showed higher values in stations between farms and downstream. So aquaculture effluent in stations between farms showed the greatest impact on water quality.

Changes in diet during the recent years have caused a marked increase in consumption of saturated fatty acids and n-6 polyunsaturated fatty acids (PUFAs) with a concomitant decrease in the intake of n-3 PUFAs. Increased fish consumption has been shown to be one of the best way to increase dietary intake of long-chain n-3 PUFAs such as eicosapentaenoic acid and docosahexaenoic acid and more balanced n-6: n-3 ratios. Our objective in this research was to characterize fatty acid profile of 7 commonly consumed fish species with different prices, from Persian Gulf. Fishes were collected from local market of Bandar abbas. Fatty acid composition of samples was determined using gas chromatography. This analysis revealed that Pomadasys kakkam and Pseudorhombus elevates contained highest concentrations of n-3 PUFA, low saturated fatty acids (42. 41%, 35%) and Pampus argennteus, as one of the most expensive among southern marine fishes contained lowest concentrations of n-3 PUFA, higher saturated fatty acids (6. 72%, 42%).

In vitro studies were conducted to assess the sensitivity of Streptococcus iniae, the etiological agent of streptococcusis of rainbow trout (Oncorhynchus mykiss) to the antibacterial drugs florfenicol (FFC) and nano florfenicol (NFFC). The isolates originated from rainbow trout (Oncorhynchus mykiss) infected with Streptococcus iniae through natural outbreaks of streptococcusis. The minimum inhibitory concentration (MIC), the minimum bactericidal concentration (MBC) and Kirby-Bauer zones of inhibition (in mm) for FFC and NFFC against S. iniae were determined. The results showed that the MIC for NFFC and FFC tested with S. iniae were 0. 078μ g/ml and 0. 312μ g/ml respectively. The MBC for NFFC were 0. 156μ g/ml and for FFC 0. 312μ g/ml. There were statistically significant difference in the MIC and the MBC between NFFC and FFC (p<0. 05). The diameter of inhibition zone for NFFC and FFC were 32. 80± 1. 1mm and 31. 63± 0. 4 mm respectively that there was no significant differences statistically (p>0. 05). It is concluded that these drugs, especially nanoflorfenicol, have a high potential for controlling Streptococcus iniae. Therefore, nanoflorfenicol can be considered as the basis for antibiotic-resistant bacteria.

Aquaculture is a rapidly growing industry in developing countries. In Sistan and Balouchestan, the land area used for marine aquaculture increased rapidly in recent years due to a steadily rising demand. The purpose of this research was conducted to identify appropriate sites for shrimp farming development in coastal of the Sistan va Balouchestan province using geographical information systems (GIS) based on creating a database of information layers of effective criteria and alternative. Data layers (Digital elevation model, slope, land use, soil thickness, distance to sea, soil type, soil pH, soil texture, distance to hatchery sites, distance to roads and distance to local markets) were gathered. The weight of criteria and alternatives were determined using an analytical hierarchy process (AHP) in EC2000 software. For modelling, spatial analysis and integration layers ArcGIS setting were used and the zoning map was obtained. By consolidation and overlaying data layers, the final map was drawn in order to classify the aquaculture development in the area in four various zones (highly suitable, suitable, moderately suitable, not suitable). The study revealed 1718 ha (1. 2%) is the highly suitable, 12547 ha (9. 4%) is suitable, 103164 ha (76. 8%) is moderately suitable and 17059 ha (12. 6%) is not suitable. This study shows that GIS databases of different formats and sources can be used effectively to establish spatial models in land evaluation for aquaculture. The land evaluation model developed in this study is useful to identify suitable areas for aquaculture in terms of efficient generation, effective conservation, and sustainable land management.

The effect of replacement of fish meal with AquPro on growth and enzymes activity on juvenile rainbow trout (weight: 2. 38± 0. 3 g) were evaluated. The fish were fed with five isoproteic and isocaloric diet for six weeks. The diets contained different level of replaced fish meal with Aqupro included 5 treatments (A=0%), (B=25%), (C=50%), (D=75%) and (E=100%). Based on the results, weight gain, relative growth rate, protein and lipid efficiency ratio in diet 50% were significantly higher than other treatments (p<0. 05), while food efficiency ratio and feed conversion ratio were shown the highest and the lowest values in diet 50%, respectively, without a significant difference than those from other treatments (p> 0. 05). The highest survival rate was revealed in the diet 75%, which was not affected by the level of AquPro in the diet. The highest activity of lipase, amylase and acid protease enzymes, respectively, from pyloric caeca, intestine and stomach were observed in diet 50%, which showed a significant difference compared to other diets (p<0. 05). The findings of growth performance and lipase, amylase and acid protease activity were revealed the diet containing 50% AquPro could be appropriate for rainbow trout growth.

A total of 4292 fish samples were caught. Sampling was carried out at 3 stations monthly, using a beach seine with 20 meter in length and 5 mm mesh size from node to adjacent node. The purpose of this research was to investigate the status of fish in the year of sampling in 1994 and compare it in 2014. A total of 9 families, 16 genera and 20 species were identified. The most species diversity was obtained from the family of Cyprinidae and Gobiidae with 6 and 5 species, respectively. Based on the results, the Shannon index ranged from 0. 924 to 1. 3622 and the Simpson index ranged from 1. 893 to 3. 158, the Margalf index ranged from 1. 258 to 2. 262 and the Pillow index varied from 0. 341 to 0. 619. This could be due to the ecological conditions of the area, the presence of canals, vegetation and proper water quality. There was a significant difference between the variability indices at different stations (p<0. 05). Also, there is a significant difference in fish length and weight at different stations (p<0. 05). The results showed that the Atherinidae with 48. 9% and Cyprinidae with 36. 94% were the most frequent. This could be due to the ecological origin of these species in the area, having shallow water, accessible food and as a natural pasture in the south-east of the Caspian Sea. Conclusion, the decrease in the coefficient of variation of 19. 3% of species has occurred over two decades, which can be attributed to the decrease in Gorgan Bay water level and its change on the biological groups in recent years.

This study evaluated the effects of different concentrations of olive leaf aqueous-alcoholic extract on growth performance and some blood and immune parameters in common carp (Cyprinus carpio) fingerlings. A total of 135 Common carp fingerlings with an average weight of 15 ± 3. 4 g were fed with two diets containing 1 and 5 g/kg of aqueous-alcoholic extract of olive leaf randomly allotted to triplicate groups with 15 fish in each group for 8 weeks. After 8 weeks, growth parameters and some hematological and immunological parameters were assessed. The results showed that there was no significant difference in final weight, final length, weight rate, specific growth rate in two treatment groups (p>0. 05). In both treated with olive leaf extract, there was a significant increase in the number of white blood cells and lymphocytes and a significant decrease in food conversion rate (p<0. 05). The highest amount of lysozyme and IgM was observed in the diet fed with 5 g/kg olive leaf extract (p<0. 05). According to the results, olive leaf extract in Gilan province, Iran, at both levels of 1 and 5 g/kg resulted in reduction of food conversion ratio and improvement of some blood and immune parameters in common carp fingerlings.

This study was performed in order to investigate effects of CuO nanoparticle (50 nm) and CuSO4, 5H2O as a disinfectant, on growth indices and gill histopathology of grass carp fingerlings. For this aims, 200 grass carp fingerlings (4. 5± 0. 5g), were divided to four treatments included: copper sulfate (1, 1. 5 mg/L), CuO– NPs) 100, 200 mg/L) and control group with triplicate, then were studied during 30 days. They were fed with 0. 8 French BioMar carp and sampled on, 5th, 10 th, 15th, 20th, 30 th day after exposure. Growth indices of fishes were analyzed by SPSS software. Also, the gill microscopic studies were done. Specific growth rate, condition index, average weight and survival respectively, in copper sulfate 1. 5 mg/L group and then CuO-NPs 200 mg/L had significantly decreased (p<0. 05). But other growth indices did not have significant differences. All treatments had gill injuries, especially in copper sulfate 1. 5 mg/L several abnormalities such as hyperplasia, congestion, deformity in secondary lamella and degeneration in primary lamella, were observed. It seems that copper sulfate 1. 5 mg/L and then CuO-NPs 200 mg/L, showed higher influence on growth indices, survival and pathological signs on gills. According to important role of gill in gas exchange, also synergy between these two substances, precise use of copper sulfate concentrations as disinfectant for any kind of fishes and necessity to consciously use of CuO-NPs is recommended.

The aims of this study were to investigate the effects of Nisin and Sodium lactate on the microbial and chemical properties of Silver Carp (Hypophthalmichthys molitrix) burger in modified atmosphere packaging andconsisted of four treatments conventional packaging (Treatment 1), CO2 50% + O2 5% + N2 45% (treatment 2), CO2 55% + N2 45 % (Treatment 3) and CO2 55% + N2 45% (Treatment 4). Samples were assayed on the 0, 3, 6, 9, 12 and 15 days with three replications during the refrigerator storage at 4° C. The parameters were microbial load (TVC, pH, TVB-N, TVBA, PV, FFA), and the results showed that with increasing levels of Carbon dioxide and Nitrogen and decreasing Oxygen levels, the amount of biochemical indices (TVB-N, TBA, PV, FFA) increased. The TVB-N, PV and FFA in CO2 45% + N2 55% (Treatment 3) and CO2 55% + N2 45% (Treatment 4) did not show significant difference (p>0. 05). Also, the microbial load in all treatments except treatment CO2 55% + N2 45% passed through the limit, 107 Log CFU/g on day 15. Microbial results showed that the treatment 4 was the best and the shelf life of this treatment was 6 days more than treatment 1.

Sponges are the most primitive multicellular eukaryotic organisms and sessile without defense organs therefore, they produce different secondary metabolites to protect themselves from predators and pathogens in their environment. This study aims to evaluation of cytotoxic properties of hexane and dichloromethane parts of methanol extract of the sponge (Ircinia mutans), collected from Larak Island. Hexane and dichloromethane parts were extracted by liquid-liquid extraction from methanol extract then tested by MTT colorimetric assay on three cancer cell lines MOLT-4, MCF-7 and HT-29. The hexane part with IC50 value 11. 53 ± 1. 3, 41. 64 ± 3. 5 and 14. 57 ± 1. 5 μ g/mL, and the dichloromethane part with IC50 value 12. 51 ± 0. 8, 26. 6 ± 2. 2 and 7. 47 ± 0. 97 μ g/mL respectively, on three mentioned cell line showed moderate to strong cytotoxic activity on all three cancer cell lines. The results also indicate that the dichloromethane part has stronger cytotoxic activity than the hexane part. This study's findings showed the potential of Persian Gulf sponges as valuable sources of new anti-cancer compounds.

The different aspects of aquaculture and biology of Tilapia have surveyed since 2008 at National Research Center of Saline Water Aquatics. In the present study, some limnological factors of earthponds and indoor tanks of Tilapia culture were investigated during the breeding season of 2016. In the earthponds, the minimum and maximum of water temperature ranges were 16. 6-27. 5 ° C and 20. 5-31 ° C, air temperature 2-27 ° C and 30-48 ° C, dissolved oxygen in the morning and afternoon 2. 11-10. 19 mg/L and 7. 06-14. 64 mg/L, pH in the morning and afternoon 8. 97-10. 9 and 9. 04-13, the depth of transparency 40-105 cm, salinity 7. 94-8. 82 ppt and ammonium density less than 0. 05 mg/L to 0. 4mg/L. The most abundant phytoplankton and zooplankton were Chlorophytes, Diatoms and Rotifers, and dominant macrobenthos were Chironomids. There was significant positive correlation between pH value with ammonium density and body length and weight, water temperature with total length, and negative correlation between dissolved oxygen and temperature and pH (p<0. 05). In the indoor tanks, the ranges of water temperature was 24-29° C, the minimum and maximum air temperature 16-30° C and 30-43 ° C, dissolved oxygen 1. 65-8. 38 mg/L, pH 7. 25-9. 37, salinity 7. 7-7. 94 ppt, ammonium 0. 16-5. 0 mg/L. There was significant positive correlation between water salinity with body weight and length and negative correlation between the amounts of dissolved oxygen with temperature, pH and total length (p<0. 05). Growth proceeding of red Tilapia was more favorable in the earth pond. Tilapia culture in earth ponds has advantages especially for using water biomass by fish and lower costs of the structures, however indoor systems are preferable because of the possibility of two growing periods per year, water conservation and environmental considerations.

Heavy metals such as Zinc (Zn) are pollutants in aquatic ecosystems that create many difficulties for the aquatic organisms and eventually humans. In the present research, sublethal effects of Zinc Chloride (Zncl2) were studied on bioaccumulation and liver structure of gray mullet (Mugil cephalus) during experimental condition. Fish were captured for experiment from Chabahar Bay with an average weight of 7. 24± 0. 5 g and total length of 6. 15± 0. 2 cm. According to the lethal concentration and LC50 for this species, a control group and two treatments with different concentrations of 1. 73 and 3. 46 mg/L, each group with 3 replicates, were used for induction sublethal concentration. Fish were exposed to sublethal concentrations for 1, 7, 14 and 21 days. At the end of each stage, liver tissue of fish were removed for histopathology examination and also on metal bioaccumulation. Result of liver tissue histopathology showed lesions such as bleeding complication, hepatocytes vacuolization and sinusoid dilation, nuclear hypertrophy, leukocyte infiltration, melanomacrophages aggregates and necrosis. Extent and severity of the lesion were increased with increasing Zinc Chloride concentration and exposure time. So that the highest lesions were for second treatment and 21 days. Also, the accumulation in the liver increased significantly with increase of the sublethal concentration (p<0. 05).

Caviar is one of the most important export products of Iran's fisheries industry. Because of the unpasteurized nature of the process, it is very vulnerable to spoilage. This study was carried out to evaluate the feasibility of chitosan, a natural antimicrobial substance which combined with other preservatives such as acetic acid, lysozyme and Natamycin (traditional and nanoparticles) to improve the caviar shelf life. The effect of chitosan coating was carefully studied within 150 days storage time at zero to-3° C in a standard situation. Both the caviar wrapped by chitosan treatments and the control sample were packed in commercial glass Jars. Microbiological، Chemical and sensory analyses were done during storage time according to the Iranian national standard. Total Viable Count of chitosan and chitosan with Natamycin 40 ppm coated caviar samples was observed to be increasing more slowly than control sample and reached 5 and 4. 8 log10 CFU/g respectively on the 150th day of storage time, while the TVC of control sample reached about 5. 3 log 10 CFU/g on the 60th day of the storage time. Results showed the effect of chitosan coating on caviar samples was to maintain their good quality characteristics and extend the shelf life of caviar significantly (p<0. 05) about 60 days in contrast with standard sample. In addition, Nano Natamycin 20 ppm is similar to Natamycin 40 ppm in terms of shelf life extension.

The aim of this study was to investigate the protective effect of pre-treatment of bacteria Pediococcus acidilactici and oligosaccharide raffinose on hematological indices of Goldfish (Carassius auratus) during exposure to nanosilver. Accordingly, 300 fish were fed for 6 weeks in four treatments. After the end of the feeding period, 50% of the lethal nano-silver concentration (0. 5 mg/L) was added to the treatments for the 14-day exposure, and blood sampling was performed. Neutrophil, monocyte and RBC indices did not differ significantly in treatments (P>0. 05), but the number of white blood cells, hemoglobin, hematocrit, eosinophil were significantly different with the control group in different treatments (P<0. 05). The results of eosinophil showed that exposure to silver nanoparticles caused a significant effect of dietary supplements and increased the amount of blood eosinophil (P<0. 05), so that the bacteria and synbiotics have the same function, but raffinose had a growth-enhancing effect. The study of hematocrit index showed that dietary supplements undergoing exposure to silver nanoparticles had a significant effect on the hematocrit index and its increase (P<0. 05), so that the bacteria and raffinose had the same function, but synbiotic was able to produce the increasing effect. The results of hemoglobin showed that exposure with silver nanoparticles had a significant effect on hemoglobin (P<0. 05). Food supplements had a positive effect on goldfish immune system and increased hemoglobin in exposure to nanosilver. The raffinose had the same performance, but the bacteria had an increasing effect. According to the results, the dietary supplement of the bacteria had the highest effect on the hemoglobin indices and it has been effective in co-administration with other supplements in the blood monocyte index. Raffinose supplementation had the greatest effect on RBC, and eosinophilic indices. Among the supplements, the synbiotic food with effect on hematocrit, white blood cell, neutrophil, biochemical among food supplements has more effect.

The positive effect of microencapsulation on tolerance simulated gastrointestinal conditions has been demonstrated by probiotics. The most important factors in reducing the viability of probiotics during passing through the digestive system are low pH in stomach and proteases and bile salts. To improve the survival rate of Lactobacillus plantarum in unfavorable condition of stomach and intestines, bacteria encapsulated with alginate/chitosan microencapsulation-emulsion. The aims of this study were to evaluate the effectiveness of microencapsulation with alginate/chitosan to carry bacteria and the survival rate of bacteria in the simulated condition of gastrointestinal tract. The microcapsules SEM technique used to study the appearance and the Particle Size Analyzers microcapsules method used to determine the size and distribution of particles. The survival rate of microencapsulated bacteria and released one in simulated gastrointestinal condition were assayed. For this purpose, they were incubated with intervals of 0, 60, 120 minutes for 48 hours at 37° C. The results indicated that dpeak was calculated 10. 4 μ m by emulsification and the average particle diameter was 2. 39 μ m. Zeta potential value in this study was +36. 2 mv. Number of microencapsulated bacteria was 2. 02± 0. 06×109 CFU/g and viability of bacteria after 120 minutes in simulated condition, digestive vices in free bacteria was 1. 59± 0. 09×109 CFU/g and in microencapsulated bacteria was 2. 03± 0. 06×109 CFU/g. The results from this study indicated that among microencapsulated and free bacteria, live-stay and enduring the conditions simulated digestive vices in encapsulated bacteria were much higher.

Mycobacteriosis or fish tuberculosis a chronic or acute, systemic, granulomatous disease in fish that occurs due to nontuberculous mycobacteria and affect all fish species. Families of Cyprinidae, Anabantidae and Characidae appears to be more susceptible to mycobacteriosis. This survey was was carried out to investigate the mycobacterial infection of ornamental fish of Semnan. 30 pieces of goldfish and 30 pieces of guppy were collected from aquarium shops of Semnan and sampled. These samples contain kidney liver and spleen. Detection of mycobacteria from extracted DNA was done, using PCR assay. Partial primer was used to identify the rpoB gene. Results showed contamination of 10% of guppies and 46. 66% of goldfish. In DNA sequencing some of the bacterial species was recognized as Mycobacterium fortuitum. In conclusion ornamental fish of Semnan are contaminated with nontuberculous mycobacteria. Considering the zoonotic risk of this disease, results of this survey is important to the general hygiene. Investigating the other areas of Semnan province is offered.