Iranian Scientific Fisheries Journal
Year:2016 | Volume:25 | Issue:3|Papers Count:31

Rainbow trout fish is highly susceptible to microbial and hydrolytic spoilage as well as oxidative rancidity. Therefore, it is essential to use preservatives to extend the shelf life of this product. Myrtle Leaf extract has significant antibacterial and antioxidant properties. This research conducted to investigate the effect of aqueous extract of myrtle (Myrtus communis) leaves on farmed rainbow trout fish (Oncorhynchus mykiss) quality during chilled (4±1oC) storage. The amounts of total phenolic compounds through Folin-Ciocalteu method, free radical scavenging by DPPH solution and metal scavenging ability of the extract through spectrophotometric method, were determined. Rainbow trout have been washed and gutted immediately after fishing. Then, with regard to primary tests results, samples were immersed in aqueous extract of myrtle leaves with concentration of 0.5% for 5 minutes. Sampling has been done at days 0, 5, 10 and 15 during chilled (4 ±1oC) storage. Antimicrobial effects of mentioned extract were evaluated by enumeration of psychrophilic bacterial counts through the pour plate method, using PCA. Furthermore, the effects of extract on chemical properties of samples have been investigated through, pH measurement, spectrophotometric evaluation of TBARS and TVB-N content determination using Kjheldal method. Sensory evaluation determined by 10 trained panelists who were asked to evaluate the appearance and color, odor, texture and eye appearance of the samples. Total phenolic compounds, free radical scavenging (IC50) and metal scavenging ability of aqueous extract of myrtle were 49.6±0.33 mg GA/ml, 20±0.03 μg/ml and 0.042 mg/ml, respectively. Dipping the fish in the aqueous extract reduced the psychrophilic bacterial count immediately after the treatment and significantly retarded the microbial deterioration of treated fishes. So that, the psychrophilic bacterial count of control and treated samples on day 10 of storage were, 7.29 and 5.91 log cfu/g respectively. Moreover, lipid oxidation and production of volatile nitrogen compounds reduced in treated samples and sensory characteristics improved compared to control samples. Thus, the myrtle aqueous extract can be used to extend the shelf life of rainbow trout during chilled storage.  The use of water as a solvent, the low required concentration of extract and abundance of evergreen myrtle bushes in Iran, provides the possibility of economic use of this extract as a natural preservative and suitable substitute for chemical compounds.

In this study the rainbow trout (Oncorhynchus mykiss) myostatin gene (MSTN) for detecting gene derived SNPs and performing genetic association study between MSTN polymorphisms and growth traits were analyzed. Twenty broodstocks of rainbow trout in Genetic and Breeding for coldwater Fishes center in Yasouj for generating full sibling were selected and tagged and then juveniles were raised at the ponds until 5 months post-hatching. DNA extract based on standard method and these individuals selected randomly for molecular analysis. Two single nucleotide polymorphisms (SNPs: g.660T>C and g.1904C>A) in intron 1 and 2 regions of the MSTN gene in rainbow trout by were identified DNA sequencing and polymerase chain reaction single-stranded conformational polymorphism (PCR-SSCP) methods. The assessment results demonstrated that 6 haplotypes were revealed in this center. Moreover, association analysis indicated that the genotypes of SNP g.1904C>A are associated with the length and body weight at 90 and 150 days of age (P<0.05), whereas no significant association was found between the SNP g.660T>C and growth traits. Our results provided evidence that SNPs in MSTN gene may be associated with length and body weight at fingerling age and MSTN gene may be used as potential candidate gene for marker-assisted selection (MAS) in rainbow trout breeding program

Due to increased bacterial resistance to common antibiotics, tendency towards using herbal extracts is increasing. In this study, antibacterial effects of the extracts of Heracleum persicum, Foeniculum vulgare, Plantago psyllium, Camellia Sinensis, Urtica dioica and Allium sativum on Yersinia ruckeri were investigated in vitro condition. The disc diffusion method, minimum bacteriocidal concentration (MBC) and determination of minimum inhibitory concentration (MIC) of the extracts against Y. ruckeri were employed to determination of antibacterial effects of extracts and furasolidon were used as standard. The MIC of extract of Heracleum persicum, F. vulgare, P. psyllium, C. Sinensis, U. dioica and A. sativum were 400, 75, 250, 250, 75 and 150 (μg/ml), respectively, MBC of these extracts was 610, 100, 500, 250, 150 and 250 (μg/ml) respectively, and diameter of zone of inhibition were 17.6±0.6 (mm), 23.6±1.2, 20.4±0.9, 18.8±0.7, 21.2±1.3 and 22.6±1.1 (mm) were, respectively, against Y. ruckeri. Results of present study demonstrated that the extracts of F. vulgare, U. dioica and A. sativum were appropriate antibacterial agents against Y. ruckeri. Based on the result of this study, using these herbal extracts were suitable alternative than common antibiotics to treatment systematic infections caused by Y. ruckeri.

Artemia Cyst is a kind of live food which has external hard cuticle which should be de membrane before usage. Artemia Cysts membrane can be eliminated with the use of capsule remover. In this study, in order to determine the most effective capsule remover, Cysts (Artemia franciscana)  were primarily exposed to 8%, 16%, and 24% levels  of chemical material including Sodium sulfate (Na2So4), Aluminum hydroxide (Al (OH) 3) and Aluminum acetate (AlC2H5O4) respectively for 10 minutes and Hypochlorite was used as the control treatment. After that, the Cysts with 2 g/l density at 27 ºC for 24 hours were hatched. The results showed that the most hatching rate (70 percent) was related to ALCOH3 and the least rate (21 percent) was related to Na2Co4 revealed a significant difference between them (p<0.05). According to the results, It is suggested to be used of Aluminum hydroxide in order to increase the efficiency of Artemia cysts (A. franciscana) hatching.

This study aimed to determine and comparison of age composition, sex ratio, growth model, and fecundity of the populations of Rhodeus amarus in Sefidrood River and Siyahrood River. In total 423 fish were caught monthly from February to June 2013. In Sefidrood River, were abundant males (58.2%) than females (41.8%) and in Siyahrood River, females (59.4%) than males (40.6%) and it was different from standard ratio (1 male:1 female). The fishes in Siyahrood River have had 1+ till 8+ years old and in Sefidrood River 1+ till 9. The average of total length and body weight was 47.9±10.4 mm and 1.98±1.4g in Siyahrood River and 56.3±7.3 mm and 2.88±1.0 g in Sefidrood River, respectively and there were significant statistical differences between these parameters in both rivers (p<0.001). Growth model in two rivers was positive allometric.  The condition coefficient of males was higher than of females in both rivers (p<0.05). The absolute fecundity was evaluated 67.9±35.2 in Siyahrood River females and 78.8±33.1 in Sefidrood River females and significant statistical difference was observed in studied rivers. Absolute fecundity had significant correlation with fish total length and body weight. The results of this study will help to increase the information available about this species.

The study is part of a research project on the southern shores of the Caspian Sea (Mazandaran waters- Kelarabad) was conducted in 2012. The aim of this study was to evaluate the effects of fish farming in cages on the distribution, abundance and biomass of macrobenthos organisms in the water at a depth of 20 meters Kelarabad. Sampling was monthly at three stations including 1 (seating cage), 2 (control with a distance of 500 m) and 3 (50 meters after the cage) using a grab with 30 cm diameter. A total of 6 groups of benthic organisms, including 2 branches, 2classes, 4 families and 6 species were identified. Overall, 23442 specimens of large benthic organisms were counted, the lowest and highest frequency at stations 1 (23.4%) and 2 (46.8%), respectively. The results showed that the highest abundance at station 2 with an average of 646.00±1230.43 N/m2 and biomass with 0.526±1.00 g/m2 in station 3, in which can be due to the lack of cage fish farming activity and the presence of big species to depend Cerastoderma lamarki, respectively. The highest abundance and biomass was in autumn with mean 888.3±1371.58 N/m2 and 0.524±0.887 g/m2 and lowest was in winter with mean 143.33±138.22 N/m2 and 0.070±0.078 g/m2. This could be related to activity fish cage culture and wintering season. The Streblospio gynobranchiata of polychaeta dominant benthic organisms with large population accounted 93.3%. This could be due to exotic species, high power compatibility and suitability related to environmental conditions. The conclusion is that the abundance and biomass of macrobenthos organisms in station 1 was less than other stations in which can be duo to concerned fish cage activity and its effects on organisms’ infauna. Therefore, it is suggested that any activity in the Caspian Sea offshore aquaculture should maintain environmental considerations and implementation of detailed environmental impact assessment (EIA) projects.

In recent decades the use of algae in the food and pharmaceutical industries is of great importance. The antimicrobial activity of brown alga methanol, ethyl acetate, hexane, and chloroform extracts on bacteria gram positive, gram negative, and fungi was evaluated by using nutrient broth macrodilution test. Sargassum glaucescense was collected around the coastal waters of Chabahar (Oman Sea) in Nov and Dec 2015. Six pathogenic organisms including; Enterococcus faecium ATCC 51299, Streptococcus mutans ATCC 35668, Shigella boydii ATCC 25923, Pseudomonas aeruginosa ATCC 27853, Klebsiella pneumoniae ATCC 13883, Salmonella enteritidi PTCC, 1709, Candida albicans ATCC 10231 and Aspergillus fumigatus PTCC 5009 were investigated by the broth dilution method. Methanolic Extract for six strains showed good activity amongst eight strains. Hexane extract, after methanolic extract has good effect on antimicrobial activity against five strains. All bacteria strain in this survey has showed resistance against ethyl acetate and chloroformic extracts. All extract of S. glaucescens has good inhibition growth against two fungal strains. S. glaucescens using four various solution extract against eight different human pathogens showed an important antimicrobial and antifungal activity. However, more investigation has to be done on separation, purification and detection of the active ingredients in order to recognize their antifungal and antibacterial activity.

Caspian Sea, Persian Gulf and the natural aquatic environment, made Iran’s geo-strategic and socioeconomic situation of the fisheries and aquaculture sector unique. This sector in the three areas of “ecotourism”, “food production” and “social behavior” play a crucial role in achieving Iran's Vision Policy of 1404 goals. However, Iran's valuable position in ornamental fish farming industry has been less attention and several issues challenged its development trend. Markazi is one of the leading provinces in this industry. So the main purposes of research were to identify current situation and providing development strategies. This study was descriptive and data were collected by survey method. The Statistical population was ornamental fish’s Producers and experts in Markazi province which due to limit number, census sampling was applied. The main tool for gathering information was questionnaire which its face validity confirmed through educational specialist and expert’s viewpoint. Also, the reliability of research tool was evaluated by Coronbach Alfa Test. The results showed that "Employment and income" and "Interest in breeding ornamental fish" were two main reasons to attract practitioners to this industry. The respondents considered the current situation ornamental fish industry, undesirable (Score 1.17 out of 5). Factor analysis showed that five factors named; "Corporate management and food resources", "management of extension and informing about authentic breeding principles", "Care Management and Insurance", "imported fish quality management" and "technical and financial support" have explained about 80% of the variance of the current situation and barriers to the development of ornamental fish industry in Markazi Province. The most important strategies to reduce facing problem in mentioned industry were development priority belonged ornamental fish industry trade system and development of specialized human resources training.

This study was carried out to evaluate the effect of replacing Dunaliella salina algae by agricultural by-products (wheat bran, rice bran and wheat/rice bran) and probiotic bacteria Lactobacillus rhamnosus on digestive enzymes activity of Artemia franciscana in a 17-day period post hatch. The study was a 4×2 factorial experiment carried out as a completely randomized design trial consisting of different dietary treatments (combinations of various substitution levels of Dunaliella salina by wheat bran, rice bran and wheat/rice bran along with probiotic Lactobacillus rhamnosus). All treatments were performed in triplicates. At the end of the trial, digestive enzymes activity was assayed. The results revealed that Artemia fed wheat bran without any dietary probiotic supplementation showed significantly higher amylase activity (2.06±0.3μmol maltose mg protein-1 min-1) (p<0.05). Treatment fed Dunaliella salina algae and probiotic showed significantly higher alkaine protease activity (7.11±0.87 U mg protein-1 min-1) and those fed wheat/rice bran with probiotic had significantly higher lipase activity (0.09±0.005 mmol p-nitrophenol mg protein-1 min-1) (p<0.05). It was revealed that dietary probiotic inclusion resulted in decreased amylase activity whilst its effect on the alkaline protease and lipase activities were totally dependent upon the feed ingredients (e.g., simultaneous feeding of artemia by Dunaliella salina algae and probiotic led to higher alkaline protease activity, while receiving probiotic resulted in higher lipase activity in group fed wheat/rice bran). Our results also showed that digestive enzyme profile of Artemia franciscana was responsive to dietary treatment. Conclusively, using wheat/rice bran in artemia pond culture would result in inferior digestive enzymes activity especially alkaline protease and lipase with subsequent effects on nutrient digestion/absorption efficiency and undesirable effects on pond productivity and final product quality.

This study evaluated the impact of dietary supplementation bacteria, Lactobacillus plantarum and Lactobacillus bulgaricus isolated from the intestine of Barbus grypus on growth performance, survival and intestinal flora of common carp. For this purpose 480 common carp (average initial weight of 40±6g) were randomly divided to 4 treatments (with three replications) and fed with diet containing 5×107 CFU/g L. plantarum (Group 1), L.bulgaricus (Group 2), Lactobacillus casei (Group 3) and a diet without probiotic supplementation (As control group) for 60 days. To evaluate the persistent of the bacteria in digestive system, from the 60 th day to 75 th day, experimental fish were fed with diet without probiotics (control). Results showed that Specific growth rate of fish fed diets containing Lactobacillus significantly higher compared with control group (p<0.05). Fish fed diets containing L.casei had significantly lower FCR than the control group on 60 th and 75 th of trial (p<0.05). The protein efficiency ratio and specific growth rate of fish fed the isolated bacteria at different times of trial was higher compared to fish fed than control diet. In general, results of intestinal micro flora assessment showed that Lactobacillus bacteria significantly increased in fish fed with dietary probiotic at 30 and 60 of trial (p<0.05) and groups 2 and 3 showed the greatest amount of Lactobacillus compared to the control group after 30 days of feeding. The results of this study showed that the addition of lactobacillus bacteria isolated from the intestines of Barbus grypus in the diet of common carp increased the beneficial micro flora population of intestinal microflora and ultimately improved growth performance and feed utilization.

The purpose of this study was to evaluate the protective effects of vitamin C and chitosan on blood biochemical parameters of common carp which are exposed to paraquat. Fish were fed enriched diet with chitosan (1000 mg Kg-1 feed), Vitamin C (1000 mg Kg-1 feed) and vitamin C combined with chitosan and were simultaneously exposed to 0.02 mg L-1 paraquat for 21 days. The results of this study showed that paraquat significantly increased aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) activities, and significantly increased glucose, cholesterol, triglycerides, urea and creatinine levels as compared with control group (p<0.05); However, paraquat decreased (p<0.05) lactate dehydrogenase (LDH), acetylcholinesterase (AChE) activities and total protein and globulin levels. Paraquat had not effect on plasma albumin levels Compared with the control group (p>0.05). Although administration of vitamin C or chitosan (alone) prevented changes in certain blood biochemical parameters in fish exposed to paraquat, the results showed that antioxidant properties of vitamin C are more than chitosan. However, administration of vitamin C and chitosan complex may prevent oxidative stress and inhibit changes in blood biochemical parameters in fish exposed to paraquat.

This study was aimed to use nano manganese oxide (Mn2O3) as a mineral premix on growth parameters followed by the erythrocyte and leukocyte properties of rainbow trout (Oncorhynchus mykiss) fingerlings. 450 specimens of rainbow trout fingerlings with an average weight of 9.1±0.3 g after acclimation to the experimental condition were randomly distributed in triplicate to five treatments of raceways ponds with open flow. Basal diet as control treatment was prepared by adding no supplemental manganese mineral. Other experimental diets were prepared by adding 4, 8, 12 mg and 12 mg nano manganese oxide followed by 12 mg manganese sulfate (as positive control treatment) to each kg diet. The Fish were fed for 8 weeks under experimental conditions with the corresponding diets. At the end of feeding trial, growth performance followed by the hematological parameters were determined by cutting the caudal peduncle (n=5). Results demonstrated no significant differences in final weigh, specific growth rate, protein efficiency ratio, and condition factor of the fish among the treatments. However, erythrocytes, hemoglobin, and hematocrit of fish fed by 12 mg kg-1 nanoparticle manganese oxide were significantly higher than fish in other treatments (p<0.05), while no significant difference was found in erythrocyte indices including mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) between the treatments. There is also no significant difference in former variables of the fish fed manganese sulfate and control diet. Findings of the present study showed that the use of nano manganese oxide increase some blood parameters of rainbow trout fingerlings including number of erythrocytes, hemoglobin, and hematocrit.

Although crystalline amino acids have not been a complete replaceable feeding source but have effective roles in success of replacements of other sources of food in diets of animals; because replacement sources usually have deficiencies that restricts using of them. These restrictions could be eliminated by using crystalline amino acids. Before conducting any research in this field, it is important to know how fish response in using crystalline amino acids in diets. In this study the efficiency of using crystalline amino acids in high proportion of diets in Sobaity sebrem was evaluated by two diets in triplicate during 42 days. The FM diets were based on fish meal and the CAA diets were based on 60% of fish meal and 40% of crystalline amino acids. There were no significant differences between two treatments in feed intake, survival, biometric indices and whole body proximate; but significant differences was observed in final weight, percent of body weight increase, specific growth rate, feed conversion ratio, protein efficiency and nitrogen retention. Whole body amino acid profile of experimental fish showed that histidine and proline were two amino acids with reduced amount in CAA treatment related to the FM. The reduction of growth and feeding factors in CAA treatments related to FM treatments shows that using crystalline amino acid in high proportion in diets of sobaity sebream need more conciderations.

In this study, the effect of commercial food replacement with earthworm (Eisenia foetida) on growth, survival, the number of larvae and their resistance to larval salinity stress in Swordtail fish (Xiphophorus helleri) was investigated. A completely randomized design experiment comprising of four treatments: T1 (100% commercial food), T2 (25% Earth worm +75% Commercial food), T3 (50% Earth worm + 50% commercial food), T4 (75% Earth worm + 25% Commercial food) were performed in triplicate. Swordtail fish were fed with 3% of its weight, 3 times per day. After a 60-day experimental feeding period, growth factors and survival rate of fish fed with different diet treatments were not affected. However, the growth factors and survival rate were affected by sex and the weight gain, specific growth rate and survival rate of females was significantly higher than males. The highest number of born larvae was observed in T2 which was significantly more than control. (P<0.05). In T4, larvae showed the lowest resistance to salinity stress test (P<0.05). Results showed that number of born larvae significantly increased in 25% replacement than control, so the Swordtail fish could be fed with low levels (25%) of earthworm without any unfavorable effects on the growth and survival rate and their larval resistance to salinity stress test.

Primary production is an important indicator of aquatic ecological systems. The spatial and temporal pattern of OPP is helpful for global climate change study. In this study the spatial and temporal variability of primary productivity in the 3 creeks of Northwest of Persian Gulf from Feb 2014 to Nov 2014 was estimated using a VGPM primary productivity model and insitu measurement. Single Peak of primary productivity appeared in April (0.356 gc/m2/d) and fall in July (0.217gc/m2/d). From the correlation analysis, we found that observed primary production has a good relationship with measured primary production (p<0.01, R2=0.60). A linear regression was then established to quantify the relationship between them. The RMSE of its function was good (0.3 mg/m3). In summary, the Landsat8 data are potentially capable of monitoring Case-II waters such as this creeks to some extent.

A total of 30 Molly fish with an average weight and length of 1.5, and 5.5 cm were collected from Jarghoyeh qanat of Isfahan province 2013. Different organs of the fish including eyes, skin, gills and intestines were examined. The results showed that 36.6% and 100% were infected by Costia and while all were infected by Ich parasite. The results did not show any correlation between fish weight and Costia load However there was positive correlation between fish weight and Ich parasite loadin thegills.

In this study we investigated biometric and morphometric traits of Capoeta buhsei in Gharachay River, Saveh. Sampling was in 5.90, 11.90 and 8.91. Sampling was by electroshoker. Samples after catching transferred to Azad university of Babols labratoar and investigated. Measurement of length was recorded by digital caliper to the nearest 0.01 mm and weight was recorded by digital balance to the nearest 0.01 g .Age determination was by observing scales in benicular loop with 40..Results of investigation of 53 male and 39 female of this species indicated that mean standard length of male and female was 131.46±23.59 mm and 152.96±25.07 mm respectively. Ratio of female to male was 0.73 :1 and with x2-test there wasn’t a meaningful relashionship between male and female ratio.

In this study the effect of different salinities on growth, biomass and pigments of Chlorophyll a and Carotenoid were tested to determine an appropriate salinity to produce maximum growth, biomass and carotenoids of microalgae (N.oculat).Therefore, the 2-liter flask contains microalga under different levels of salinities (20, 25, 32, 35, 50 ppt), and under laboratory conditions( temperature 25-22oC, PH. 8, and light period of 12 h light and 12 h darkness) were cultured for 14 days. The results of present study indicate that The maximum growth of microalgae (72.63×106cell ml–1) and the maximum specific growth rate of microalgae (0.33 d⁻1) included in treatments with salinity of 25 and 30 ppt, that had a significant difference with the other treatments (p<0.05) .The maximum dry weight (0.022 g/lit) and amount of chlorophyll a (3.92 mg lit) was recorded in treatments with salinity of 30 ppt and shows significant difference with the other treatment (p<0.05). The Minimum amount of carotenoids (0.41 mg lit) was related to treatment with salinity of 50 ppt. shows a significant difference with other treatments (p<0.05).According to the results we can say that microalgae resistant to high salinity and a wide range of salinity has the ability to grow and produce carotenoids.

In this work the effect of different concentrations of chitosan (1 and 2 %), essential oil (EO) of Pistacia atlantica subsp. kurdica (1 and 2 %) and chitosan –EO (1 % chitosan + 1 % EO) on the lipid oxidation indexes (peroxide and Thiobarbituric acid (TBA)) and also the percent of moisture and free fatty acids in fish were determined during storage. During the storage period the coating contains a combination of EO and chitosan (1% chitosan + 1% EO) in compared with other coatings had the highest content of moisture and the lowest amount of free fatty acids, peroxide and Thiobarbituric acid index and had the best situation in reduction oxidative rancidity.