فصلنامه شیلات
سال هفتاد و سوم شماره 3 (پاییز 1399)

Microplastic (MP) sorption and transfer of chemical contaminants has been widely reported, yet few studies have investigated combined effects of contaminant-loaded MPs on organisms. Microplastics can act as carriers of environmental chemical pollutants and pesticides. Absorption of these particles by living organisms, especially aquatic organisms, causes changes in the activity of enzymes in the antioxidant pathway and peroxidation of membrane lipids. The aim of this study was to investigate the microplastic effect of polyethylene terephthalate and abamectin pesticide alone and in combination on glutathione peroxidase ‎(GPX) ‎activity and lipid peroxidation of zebrafish. In this study, zebrafish were exposed to a concentration of abamectin (0.006) and two microplastic concentrations of polyethylene terephthalate (5 and 10) and Their combination ‎(0.006 mg L-1 ABM‏ ‏+5‎‏ ‏mg L-1 PET) and ‎(0.006 mg L-1 ABM‏ ‏+10 ‏mg L-1 PET). In this study, the activity of glutathione peroxidase and malondialdehyde (MDA) were evaluated as indicators of lipid peroxidation. Analysis of results by one-way ANOVA method and significance of Pvalue <0.05 showed that the amount of malondialdehyde in treatment (0.006 ABM)was significantly decreased compared to the control and glutathione peroxidase activity in treatment 0.006 ABM +5 PET  treatment 0.006 ABM +10 PET was significantly increased compared to the control group. Also, analysis of the results by Two-way ANOVA method showed interaction in 0.006 ABM +10 PET treatment in glutathione peroxidase enzyme and this effect was not observed in other combination treatments.

Fishmeal factories produce a large amount of wastewater during the production process, which contains protein. The aim of this study was to recover protein from the effluent of fishmeal factory by isoelectric method and investigate the functional properties of recycled protein. The effluent sample was obtained from fishmeal production plant in the Konarak city and proximate composition analysis of the effluent sample was investigated. The protein in the effluent was recycled using the isoelectric precipitation method and pH changing. The functional properties of the recovered protein including solubility, oil and water holding capacity, emulsifying index and emulsion stability, foam formation and foam stability were measured using standard methods procedures. The results showed that the amount of protein in the treated sample has no any significant differences under the effluent effects (p >0.05). The highest and lowest solubility were obtained at pH 2 and pH 6, respectively. The water and oil holding capacity of recycled protein was 0.45 and 0.4 ml/g, respectively. The highest emulsion activity was observed at pH 10 and the highest foam formation capacity at pH 2. The highest emulsion stability was observed at pH 2 and the highest foam stability was observed at pH 2 and 10. Recycled protein showed good functional properties and changed with pH, but not all properties followed a specific trend.

The port state jurisdiction in preventing the unloading of illegal fishing in the port by foreign ship is the result of years of inefficiency of the exercise of the competence of coastal state and the flag state in accordance with the provisions of the Convention on the Law of the Sea. However, the port state jurisdiction’s components in fight against illegal fishing for foreign vessel faces challenges that its study is one of the objectives and goal of this article. The research method is descriptive-analytical and based on the provisions of the Convention on the Law of the Sea and the Food and Agriculture Organization’s documents related to the port state jurisdiction and the fight against illegal fishing. The main question of the research is what are the components and challenges of the port state’s jurisdiction in fighting illegal fishing of foreign ship and preventing the unloading of caught products? The research findings show that the components of port state’s jurisdiction depend on membership in the Food and Agriculture Organization’s international documents and compliance with its criteria in domestic law. This situation is a combination of international and domestic requirements related to the port state and its measures to combat illegal fishing of foreign ship and preventing the unloading of caught products, some of these requirements have been complied with in the Law on Protection and Exploitation of Aquatic Resources of the Islamic Republic of Iran. But in some cases, the coastal state and the flag state are in conflict with each other, which requires tripartite cooperation of the port, coastal and flag states in different maritime areas under their special jurisdiction and supervision of the Regional Fisheries Management Organization.

This study was conducted to evaluate the interactive effects of different levels of dietary ascorbic acid and density on growth parameters of rainbow trout. The eighty- one rainbow trout broodstock (812 ± 1.5 g) distributed into six groups as experimental treatments and were fed different levels of ascorbic acid including 0, 100 and 1000 mg/kg L-ascorbyl-2-polyphosphate. The feeding trial was carried out in two different densities (3 and 6 fish/m3) for a 16- week period in triplicates. Each diet was fed to triplicate groups of fish to apparent satiation two times a day. Changes of body weight increase were observed from fourth week to 12th week. The highest amounts of weight gain and specific growth rate were observed in high density (6 fish/m3), but no significant difference was observed between 100 and 1000 mg/kg ascorbic acid in high density. At the end of the experiment, fish fed −C diet had a lowest final mean weight (885.2 ± 2.09 g) than those fed +C diet. These results indicated that dietary ascorbic acid significantly influenced growth performance of rainbow trout broodstock, especially in high density and the level of 100 mg ascorbic acid per kilogram diet can lead to desirable growth of female rainbow trout breeders.

The questionnaire was used as a tool to examine the differences between the views of sellers and buyers of fish in the large fish market in Tehran. ...... The Chi-square test was used for the percentage of responses and the Kruskal-Wallis and Mann-Whitney U test to identify the relationship between sociological factors and to compare the two groups studied with mixed marketing factors. The results showed that buyers born in the northern provinces and people with lower age, education and income and without jobs are more sensitive to price and the opposing groups are affected by the place of distribution or sale. Sellers differed from the group of buyers in terms of price and location.., Fresh fish was the most important factor in shopping. Contrary to the sellers' view, the fish price was not the main factor in the return to the market, and the diversity and accessibility of the market were the factors that attracted customers to the market. Sellers emphasized the perceived value of the product, how to clean and catted it, the convenience of visiting and accessing the purchase and promotion of the market on billboards, media and publications to further improve the market. Contrary to the sellers' opinion, the buyers believed that the market was characterized by quality and freshness, fish species and health of the product, price of fish, cleanliness and health of the market, holding a food festival and fish cookery course training and awarding prizes and lotteries. . .... Therefore, in addition to the need to pay attention to the views of buyers, sales by the producer in the market, allocation of government subsidies, inserting the location of fishing and aquaculture and installing electronic signs, the amount of entry and exit of fish in the market should be considered.

Today, the replacement of plant extracts instead of chemical preservatives in the diet has been considered with reducing the adverse effects of chemical preservatives. In this study, the effects of black grape seed extract on growth, intestinal and liver histology, as well as gastrointestinal enzymes, in common carp were investigated. Grape seed extract (30g kg-1) was added to the basal diet and at the end of the experimental period, the digestive enzymes, including lipase, amylase, and trypsin, were measured. The fish were also dissected, then intestine and liver were collected and fixed for histological studies. The results showed that among different digestive enzymes, only lipase had a significant increase (1.67±0.10 U/mg protein) compared to control group (1.35±0.04 U/mg protein). In the intestinal and liver histology, supplemental diet did not have any side effects on the normal structure. The ratio of villus height to the distance between two adjacent villus in the basal part was slightly higher in treated fish (17.39 ± 0.5μm) than the control group (16.71 ± 0.59 μm), but no significant differences was observed. Also, the number of goblet cells in control group (4.59±0.17μm) was slightly higher than treated fish (4.09±0.21μm), however, no significant difference was observed. Morphometric study in liver also showed an increase in hepatocyte size (24.01±0.16µm) compared to the control group (23.42±0.14µm). In general, the increase of the digestive enzyme activity and healthy liver and intestine structure could show the potential of grape seed extract as a beneficial feed additive in common carp.

Giant freshwater prawn is one of the most important commercial species in aquaculture. Although many nutritional studies have been done in the field of giant freshwater (Macrobrachium rosenbergii), but no study has been conducted on the effect of ginger powder on the growth and survival of freshwater prawn. Hence a nutritional test has been conducted with iso-protein and lipid level (30 & 7.6%). Ginger powder with different levels of zero (control),2, and 3 percent has been considered in the diet of prawn. 120 juvenile prawn with average weight (40 g) randomly shocked in 12 aquarium glass tanks of 40 L capacity which has been filled with 30 L fresh and filtered water. Juvenile prawns fed daily 4 times (6,12,8 and 20). Growth performances such as weight gain (WG), Specific Growth Rate (SGR), Food Conversion rate (FCR), Protein Efficiency (PE), and Survival Rate (SR) were evaluated. Based on statistical analysis, it was shown that with increasing ginger (Zingiber officinale) 3% level in the diet and nutritional factors that improve (p < 0.05). Environmental shock such as temperature and salinity were tested in different treatments. The prawn's mortalities, due to high temperature (32°c) and salinity (15ppt) were least in treatment with 3% ginger powder. From the result of this experiment can be inferred that the growth, survival, and environmental stressing is more reliable in prawns diet containing a 3% level of ginger powder.

In this study, in order to investigate the effect of oral and combined gum coating and thyme extract on keeping vanilla shrimp in cold storage conditions (1.4° C), different treatments including: 1-control (immersion in distilled water and without coating), 2- coated treatment Consumed with 1% thyme essential oil, 3-1% coated gum-coated treatment and 4-combined treatment with 1% thyme-coated essential oil - 1% dehydrated gum, were tested every 4 days for a period of 12 days. Microbial tests; Counting the number of enterobacteriaceae and chemicals; TBA and TVN values ​​were measured and melanosis was evaluated as well. With increasing in the retention time, the enterobacteria, TVN, TBA values ​​and melanosis intensity significantly increased in the control treatment (P <0.05). The effect of 1% thyme coating and combined treatment on the number of enterobacteria was significant and could control the enterobacteria during the storage period (P <0.05) and Zedo gum-coated treatments did not have any significant effect on controlling the samples against texture corruption as well.

The role of Activin-like factors in pluripotency maintenance is unknown during the zebrafish development. In this study, the embryos were treated with Activin A after dechorionation. Nanog and Oct4 expression patterns were evaluated during 256-cell, 1K, oblong, dome and shield stages (three replicates per stage). Due to the activation of cell signaling pathways before ZGA (zygotic genome activation), Activin treatment led to higher phosphorylation of Smad2/3 and progressively higher rate of Nanog expression in comparison to the control group at 1K-cell stage. At the oblong stage Nanog mRNA levels significantly decreased, therefore, Nanog mRNA levels should be reached to its peak in earlier time. Activin-like factors enhancement decreased Oct4 mRNA levels in contrast with Nanog. Due to the conservation of Activin-like factors pathway, the results can be generalized to other vertebrates and also provide a background for further studies, because of the stem cell importance.

Synthetic preservatives have been used as food additives to extend shelf life of foods, but they are strictly regulated due to toxicological concerns and some health problems. So, it is increasingly attractive to find out effective and nontoxic measures (e.g. use of natural antimicrobial agent) to delay microbial spoilage. Considering the high probability of Escherichia coli contamination of local fish, the present study aimed at investigating the effects of aqueous and ethanol extracts of pomegranate peel (Punica granatum) on the growth of Escherichia coli in minced common carp during refrigerator storage. The minced meat treated with different concentrations of water and ethanol extracts of pomegranate peel, and the sensory evaluation were performed. After determining the optimum concentration, the treated minced meat inoculated with 1×103cfu/g Escherichia coli. The treated samples packaged separately into sterilized bags and stored at (4±1) °C, then Counting the bacteria was performed at days 0, 1, 3, 6, 9 and 12 after storage in refrigerator. The results showed that treatment containing 20% ethanol extract significantly could eliminate the bacteria after the 24- hour period, then followed by 10, 12/5 and 15%. The aqueous extract antimicrobial activities showed a very weak role and the number of bacteria had a rising trend. The results of this study indicated that the aqueous and ethanol extracts of pomegranate peel at high concentrations, because of antibacterial, antioxidant and preservative properties, could play an important role in ensuring food safety and consumer play.

Nowadays, due to the overuse of antibacterial substances, some strains of bacteria showed a resistance to them. Hence, it is necessary to use new effective methods to control diseases caused by these strains. Yersiniosis that occur in some aquatic species, is caused by Yersinia ruckeri, a Gram-negative rod-shaped enterobacterium. In recent decade, a new approach developed to control pathogen using synthetic polymers with antibacterial properties, one of this synthetic polymer is Polyethyleneimine (PEI) that many studies reported its antimicrobial properties in aquaculture activities. Thus, the purpose of this study was to control Yersinia ruckeri by impregnating the zeolite with Polyethyleneimine and install it as an antibacterial filter in the fish tank. In this study, clinoptilolite zeolites with two concentrations were used, the first sheet(I) containing 15g of zeolite activated by 30 ml of toluene and then added it 1ml of EPO and 1ml of PEI, for the second sheet(II), the same procedure was run, but 2ml of EPO and 2ml of PEI were used, after that both sheets stirred under heat to give the desired agent and then transferred to the zeolite to produce the substrates treatments as two kinds of filters. Then ability of two anti-bacterial substrates tested to remove Yersinia ruckeri in the presence of the minimum bactericidal concentration (MBC). The growth inhibition zone also tested at concentrations of 1.8×108 to 1.8×101 CFU/ml-1 and 1.8×104 CFU/ml-1. The results showed that zeolite coated with two concentrations of PEI polymer have the potential to remove Yersinia ruckeri at 1.8×103 to 1.8× 101 CFU/ ml-1. The bacterial concentration decreased by 54% and 70% at the bacterial concentration of 1.8×103 CFU/ml-1 for zeolite coated with concentrations of I and II, respectively. Also, the growth zone diameter positively correlated with zeolite weight, the growth zone diameter for 0.05g zeolite by concentration I and II were 10.7,11.3 mm, and for 0.1 g were 15.23, 15.88 mm and for 0.15g were 18.75, 19.11 mm respectively. Finally, it was concluded that the PEI polymer-impregnated zeolite, as an antibacterial substrate, exhibits its best appliance at the bacterial concentration of 1.8× 103 CFU/ ml-1.

Water resources pollution with detergents is one of the most serious subjects in the health and well-being of aquatic ecosystem fields The consequence of entry of detergents into the waste-water in terms of the occurrence of phenomenon of trophic and indestructibility of the hard detergent groups and foam formation, etc. cause pollution of the environment and water resources. Increasing the concentration of these substances in water sources has adverse effects on fish and other aquatic organisms. The aim of this study was to investigate the effect of some commonly used anionic detergents on embryo cortisol levels and then larval abnormalities and hatching percentage in zebrafish (Danio rerio</em>) while exposed to them. For this purpose, fertilized zebrafish eggs were exposed to various detergents (dishwashing liquid as a detergent, washing powder as a cleanser and sodium hypochlorite as a bleach) with concentrations of 1, 1, 0.25 ppm, respectively. To measure the level of cortisol in three stages of, cell division (cleavage), gastrula and hatching, samples were taken from the growing embryos and their cortisol levels were determined. After hatching, the larvae were sampled at different times (5, 10 and 15 days after hatching) and their abnormality was determined. The results show that in terms of the percentage of abnormalities (enlargement of the head, curvature in the dorsal region and tail) and cortisol concentration of treatments exposed to detergents were significantly different from control groups (P < 0.05). So that the most abnormalities (Control 6.67, washing powder 36.67, dishwashing liquid 20, bleach 13.33) were observed in the washing powder treatment. Also, cortisol levels increased from fertilization to gastrula stage and then decreased until hatching, although the amount of cortisol in the control groups decreased from fertilization to hatching (from 4.8 to 3.2 ng / ml). generally, it can be concluded that increasing the use of detergents reduces the success of reproduction and causes abnormalities in aquatic species.

Significance of climate change trend in the period of 22 years and the effect of climatic variables on CPUE of pelagic fishes (sardines and anchovies) in three areas: Jask port, Lenge port and Qeshm were studied. Three categories of data including fishing, satellite and meteorological data were processed and analyzed over a period of 22 years (1997 to 2019). Satellite data related to water areas were used to obtain information on sea surface temperature (SST), sea surface chlorophyll (SSC) and photosynthetic active radiation (PAR) variables. Information about meteorological data including wind speed, rainfall and minimum and maximum temperatures were received at 3 offshore and coastal stations. CPUE values ​​were significantly different in the three study areas. The most significant changes were observed for the mean maximum temperature and minimum temperature of the months. So that in each of Jask and Lenge regions in 6 months of the year and in Qeshm region in 9 months of the year, the trend of maximum temperature changes in the desired time period has increased significantly. During the period, the average monthly minimum temperature of 3 months of the year in Jask region, 6 months of the year in Lenge region and 10 months of the year in Qeshm region has increased significantly. The fishes of Qeshm and Lenge regions showed high overlap with each other, while the fish of Jask region showed a more distinct difference than the other two regions in the PCA diagram. The relationship between CPUE changes and environmental parameters was almost the same for both species. In all models, chlorophyll A and rainfall were the most significant and important variables affecting.

In the present study the effects of five- strain probiotic blend (Bacillus</em> spp.) with concentration 1×108</sup> CFU/ liter against stress responses, due to expose to high stocking density (30, 45, 60 and 75 larvae per 10 liters of water) on Oncorhynchus mykiss </em>larvae were investigated in triplicates. The growth factors and hematological parameters were recorded as well. The larvae with the mean weight of 0.235±0.08g introduced in each experimental unite and fed the experimental diets and reared for a 45- day period. At the end of the experiment, the maximum growth and feeding rates were obtained in the treatment with a density of 60 fish larvae per 10 liters (fed from a diet supplemented with Bacillus) and the minimum rate significantly obtained in the treatment with a density of 45 larvae per 10 liters compared to other experimental treatments (p < 0.05). However, there were no significant differences among treatments containing 30, 60 and 75 larvae per 10 liters of water (p>0.05). The results of hematology indices, WBC, RBC, Ht, Hb, MCV, MCH and MCHC increased significantly with an increase in the density of fish larvae among the experimental treatments and their highest levels were obtained in treatment with a density of 75 fish per 10 liters. The serum glucose levels increased significantly while the fish density increased and it was higher in 60 and 75 fish per 10 liters treatments compared to 30 and 45 fish in 10 liters densities. Overall, the findings of this study showed that despite the effects of fish density, the use of probiotic bacilli also affecting on some growth, nutritional and blood indices.

The present study was to evaluate changes in microbial, TVB-N (volatile nitrogen bands), sensory evaluation and also the freshness index of carp (Ctenopharyngodon idella) fillet packed in at fillet packed in modified atmosphere (CO2 55% + N2 45%). . Microbial load parameter changes (national standard no. 2325), TVB-N (quasi-quantitative method), recently (K-value which includes the TP + ADP + AMP + IMP + HX + HXR) and its related psychological indicators (chromatographic HPLC machine) were investigated. The quality of the grass-fiber fillet packed in modified atmosphere showed a significant difference in time and temperature (p < 0.05) and with increasing time from 5 to 15 days and from 0 to 12 °C, these parameters showed an incremental (p < 0.05). Two indicators IMP and temperature decrease with increasing time and HxR (p < 0.05) and the lowest value on the day 15 and the temperature of 12 °C (p < 0.05). Grass Carp fillet was favorable at 0 ° C until the 15 day and at 6 ° C until 5 day, based on microbial indices, volatile nitrogen beds and novelty index for human consumption, but based on these indices at 12 ° C on days 5, 10 and 12 it was in unfavorable conditions. Temperature and time had a significant effect on all measured indices (p <0.01). Regarding the F-value, in all indices temperature was more effective than index time. The suggested formulas for all the indices studied in the experiment (dependent variables), had a correlation coefficient (R2) and modified explanatory coefficient (R2 -adj) close to 1. The proposed formulas for each indicator were able to predict the quality changes of Chenopharyngodon idella fillet packed in modified atmosphere with low error explanatory coefficient (R2 -adj) close to 1.

Due to the importance of probiotics in marine shrimp farming, this study aimed to investigate the effect of Bacillus subtilis and Lactobacillus plantrum probiotics in breeding water on growth factors and carcass quality of Vanami shrimp. In this study, the interactions of two probiotics Bacillus subtilis (B) and Lactobacillus plantarum (L) at 2 levels B1 = 106 CFU / gr and B2 = 106 C 3 CFU / gr, L1 = 105 CFU / gr and L2 = 105 × 3 CFU / gr in the water of western white-footed shrimp post-larval breeding tanks was evaluated for 2 months. Growth factors including: body weight gain, feed conversion ratio, survival percentage and carcass fat and protein were measured, then the shrimp were transferred to the freezer at -18 ° C and on days 1, 15, 30, 45 and 60 Carcass quality including: drainage, water holding capacity, pH, TBA and TVB-N were measured. According to the data obtained from carcass quality tests, it was found that in the gut index, on day 1, Lactobacillus plantarm strain alone and in combination with Bacillus subtilis was effective in significant differences, on day 60, only Lactobacillus plantarm species in The difference was significant. In the water holding capacity index, only in the results related to the first day of the experiment, the role of both strains individually and also the interaction with each other was observed, while the pH results had no role at all in either day. In TBA test, only Lactobacillus plantarm strain was effective in the data related to day 15, while in TVB-N index, like pH, they were not affected in any of the days.

The current study was performed to examine the efficacy of dietary- black cumin (Nigella sativa) oil on the growth rate, some antioxidant and biochemical parameters, as well as digestive enzyme activity in electric yellow cichlid. Fish (1.29 ±0.08 g) were divided into three groups and fed the diets containing 0, 1% and 1.5% black cumin oil for 50 days. Results showed that growth performance was enhanced in the treatment groups compared to the control group (p < /em> < 0.05). Among different antioxidant indices, higher total antioxidant activity was observed in the treatment group fed fed the diets containing 1.5% black cumin oil (p < /em> < 0.05), but lipid peroxidation product, indicated by MDA, was not altered compared to the control group. Meanwhile, activities of some antioxidant enzymes, including superoxide dismutase and catalase in both treatment groups and glutathione S-transferase in group fed fed the diets containing 1.5% black cumin oil were higher compared to the control group (p < /em> < 0.05). During this experiment, higher protein level was also recorded in the treatment groups (p < /em> < 0.05), but no significant changes were noted in alanine aminotransferase level in comparison with the control group. Feeding with black cumin oil also led to a significant increase in amylase and acid phosphatase activities (p < /em> < 0.05), whereas no significant changes were noted in lipase and protease activities. Therefore, the results show that the administration of black cumin oil, especially at 1.5%, had the potential to improve the growth rate, some antioxidant indices, as well as digestive enzyme activities in electric yellow cichlid.

Oil-in-water nanoemulsions based on vegetable oils have extensive antimicrobial properties against bacteria, viruses, fungi and spores due to their ability to destabilize the lipids in the cell wall of the organism. For this reason, their application has been considered as a way to increase the shelf life of fish during the chilled storage. In the present investigation, the effect of oil-in-water nanoemulsion of sunflower oil on the quality and shelf life of rainbow trout fillet during twelve days of refrigeration storage was investigated. After preparing the fillets, the samples were coated with a sunflower oil nanoemulsion and then refrigerated for twelve days, then at four-day intervals (0- immediately after coating treatment-, 4, 8 and 12 days) were evaluated for some quality indicators (thiobarbituric acid, TBA), total volatile nitrogen, TVB-N; water holding capacity, WHC; & color parameters (including brightness L</em>*, redness a</em>* and yellowness b</em>*). Uncoated fillets were considered as control set. The obtained results showed that coating the fillets with nanoemulsion of sunflower oil had a significant effect on most of the studied indicators (P <0.05) and resulted in better protection of the fillets against spoilage conditions. Therefore, according to the achievements of the present study, it is recommended to cover rainbow trout fillets with sunflower oil nanoemulsion when chilled storage is used to preserve them.