نشریه علوم آبزی پروری ایران
سال دهم شماره 1 (بهار و تابستان 1401)

Increasing the use of nanomaterials leads to the release of these particles in aquatic environments that can have effects on aquatic animals, therefore, the present study aimed to investigate the toxicity of titanium dioxide nanoparticles produced by the Chemical and biological method on Xiphophorus maculatus. First, the survival rate of fish under similar conditions to toxicity experiments were investigated  and then Xiphophorus maculatus fish to determine the intermediate lethal concentration (LC50) of nanoparticles in 12 treatments (each with three replications) including 6 treatments containing concentrations of 0, 80, 160, 320, 640 and 1280 mg /L nanoparticles titanium oxide produced chemically and 6 treatments containing concentrations of 0, 240, 480, 960, 1920 and 3840 mg /L titanium dioxide produced biologically method in 60 liter tanks with 15 fish per treatment were exposed for 96 h and fish mortality were recorded at 24, 48, 72 and 96 h. Survival tests showed that up to 96 hours after stocking fish, no mortality were observed and the survival rate was 100%. With increasing the concentration of nanoparticles and increasing the exposure time, the percentage of fish mortality increased. The intermediate lethal concentrations (LC50) of titanium dioxide nanoparticles produced by chemical and biological methods during 96 h of exposure were 255.49 and 720.76 mg/l, respectively. Based on the results of the present study, chemically produced nanoparticles are more toxic than nanoparticles produced biologically method.

This study was conducted to evaluate the effects of different levels of Cyanothece sp. on growth indices, survival rate and feed conversion ratio of western white shrimp (Litopenaeus vannamei) for 60 days in Chabahar fisheries research center. 240 individual with an average weight of 3.03 ±0.017 g were distributed in 12 tanks with a density of 20 shrimp per liter of storage. Treatment were 0 (control), 100 (treatment 1), 200 (treatment 2) and 300 (treatment 3) mg/kg extract of Cyanothece sp. Growth indices were examined including mean weight, total length, specific growth rate, feed conversion ratio, feed conversion efficiency and survival as 3 meals per day and at the end of the period. The results showed 200 mg/kg of microalgae extract had a positive and significant effect on survival parameters (P<0.05). Mean weight, length and specific growth coefficient (SGR) of shrimp fed a diet containing 200 mg / kg of extract 13.88 g, 13.03 cm and 2.56% were significantly higher than the measured values in other treatments, respectively. While due to the significant increase in feed conversion ratio (FCE) in shrimp treated with 200 mg / kg, the rate of feed conversion ratio (FCR) was significantly lower than other shrimps. It is concluded the use of microalgae extract can have a positive effect on growth rate, survival rate and persistence of young western white shrimp.

The restoration program of Caspian kutum (Mahi Sefid) stocks was carried out by the Iranian Fisheries Organization about four decades ago, following its catch reduction in the early of the last century. Despite releasing about 150 million juveniles annually, the catch has always fluctuated and the average catch has never exceeded 10,000 tons. In addition, expected diversity and biomarkers in newly released stocks, such as length and weight, and growth and reproduction indices have also declined. In the present study, the strengths, weaknesses, opportunities and threats of the program for breeding and release of Mahi Sefid in the Iranian waters of the Caspian Sea have been investigated using the SWOT-FAHP method. The results show that although strengths outweigh weaknesses that the biological, social and economic values of Caspian kutum and the existence of specialized hatcheries with the presence of experienced experts are the most important strengths. In contrast, the threat points outweigh opportunities, and in general it can be acknowledged that this situation requires strategies to reduce threats. Therefore, strategies to improve the process of rebuilding Caspian kutum stocks were developed and prioritized by the Quantitative Strategic Planning Matrix (QSPM), which among the identified strategies, contingent (conservative) strategies have the highest score, and accordingly, providing and strengthening breeding infrastructure, especially Natural reproduction in migratory rivers, participation of non-governmental organizations in the protection of local rivers, use of equipment of hatcheries and reconstruction of reserves and updating of worn-out equipment in order to continue the process of artificial reproduction due to pollution and destructive factors in some Rivers, gene bank formation, implementation of breeding program and application of research results on the time frame of fishing and standardization of fishing equipment, scored the most points among contingency strategies.

Algae have the most important role in the production of fresh and marine aquatic animals especially at the stage of larvae culture due to their nutritional and also industrial components such as protein, unsaturated fatty acids, and pigments. Therefore, the researchers trying to improve the production of these micro-activated bio-cells with formulating the new media. This study, aims to investigate production of Nannochloropsis sp. (biomass production) under small scale and batch culture condition, using commercial agriculture fertilizers vs. and analytical grade salts for a period of 20 days. Five different culture media were formulated as treatments. Four concentrations (100, 75, 50 and 25%) of Cooper hydroponic culture media were tested and compared to F/2 medium that is commonly used for microalgae culture. Production of Nannochloropsis sp. Showed better results in 25% medium from eighth to twentieth days of experiment period. In the last day, cell production in treatment with 25% of copper formula (23.45×106±2.001×106 cell/ml) did not show any significant differences than F/2 medium (17.15×106±1.202×106 cell/ml) (P>0.05). The Medium 25% was also highly economic and capable for production of Nannochloropsis sp., since it showed almost 94% (sixteen times) cheaper than F/2 medium (excluding the cost of F/2 analytical grade vitamins) during formulation.

Isolation and identification of unknown microorganisms native to our country and their preservation in the collections of genetic resources in order to exploit their biological capacity are of special importance and necessity. This study aimed to identify halophyte microalgae living in the back-barrier Lipar located on the shores of the Oman Sea in Sistan and Baluchestan Province. Water and phytoplankton sampling was carried out from the back-barrier in 2019-2020. Isolation and purification of the collected microalgae were performed by serial dilution and F2 medium culture in agar and liquid media, and finally, pure single colonies were obtained. Then, the initial identification of isolates was done through microscopic observations and comparison with morphologically valid classification keys. In the next step, 18S rRNA and 16S rRNA genes were used for further verification and identification by molecular method and sequencing. Analysis of morphological data and molecular sequencing showed that two purified isolates were green microalgae Dunaliella salina and green-blue microalgae Cyanothece sp., which was identified for the first time from the back-barrier. In terms of biological and commercial capacity, these two microalgae are suitable species for mass production and are widely used in industry. The purified strains have been donated to the National Bank of Iran Genetic Resources for future research or industrial-scale exploitation.

The genus Peronia Fleming, 1822 by having 14 species, is one of the most diverse genera of the Onchidiidae family, which is highly distributed in the waters of the Persian Gulf and the Sea of ​​Oman. Despite their important ecological role in these areas, unfortunately, they have not been well studied so far. In this study, while describing the morphological characteristics of two species of this genus, Peronia madagascariensis (Labbé, 1934) and P. verruculata (Cuvier, 1830) with the help of a fragment sequence of a cytochrome oxidase gene, their status was determined. In this study, for the first time radulla belonging to the members of this genus in the northwestern Indian Ocean region were photographed and P. madagascariensis was reported from Iranian waters of the Oman Sea.

The tissue regeneration due to its attractive nature and potential applications in human diseases has always been in the focus of research. Determining the cellular and molecular mechanisms involved in the regeneration process in model organisms that perform well regeneration can help us to developing strategies for tissue repair and regeneration in species such as humans that have low regenerative capacity. MicroRNAs, are small, non-coding RNAs that play a key role in controlling the expression of genes that conduct tissue regeneration by inducing overexpression or inhibition. Various experiments have been performed to identify the types of microRNAs that conducte regenerative responses. Due to the exceptional ability of the zebrafish (Danio rerio) in the process of self-healing of damaged tissues, this model has been considered as the focus of regeneration researches. In this article, we intend to review the latest findings on the effect of microRNAs on the fin, heart and eye regeneration process of zebrafish by regulating gene expression. The future prospects and further development potential of this fascinating research field will also be discussed.

This study was conducted to evaluate the effects of dietary L - Lysineon and L - Carnitine on growth and survival and some blood biochemical parameters of Oncorhynchus mykiss fry. For this purpose, Oncorhynchus mykiss fry with a mean weight of 25 gr in 10 treatments with 2 replicates were distributed randomly in 20 tanks. The L – Lysineon and L - Carnitine diet was added to diets at different levels. The breeding period was considered to be 8 weeks. Growth indices, survival rate and blood biochemical indices and safety factors, as well as comparisons between treatments at the end of breeding period blood sampling was performed. The results showed that the treatment fed L – Lysineon 0.5 and L – Carnitine 1gr/kg diet of L – Lysineon and L – Carnitine material had significant differences with the control group in the final weights, weight gain, body weight gain percentage and reduction in feed conversion ratio (P<0.05). In terms of survival rate of fish, the highest survival rate was observed in treatments containing different levels of L – Lysineon 0.5 and L – Carnitine 1 gr/kg.  The results showed a significant difference between plasma biochemical factors such as glucose, triglyceride, and cholesterol in levels of L – Lysineon 0.5 and L – Carnitine 1 gr/kg. (P<0.05). The highest amount of total protein, albumin, and globulin was observed in this treatment, which significantly differs from the control treatment (P<0.05). As a general conclusion, it can be stated that the use of L – Lysineon 0.5 and L – Carnitine 1 in the Oncorhynchus mykiss fry diet can increase and improve the growth, survival index and stimulate the immune system and thus improve health and physiological status of Oncorhynchus mykiss.The addition of L – Lysineon 0.5 and L – Carnitine 1 of feed for Oncorhynchus mykiss fry are suggested.

Microalgae are one of the safest sources of protein production in the world that have good sources of a wide range of beneficial compounds, including proteins, fats and pigments. This research aims to use the cultivation of Dunaliella salina in Modified Johansson (DUM) and Guillard (f/2) media under salinity stress of 10, 20, 30%, culture media efficiency and the effect of salinity stress on Chlorophylls a and b as well as total carotenoids should be investigated. The results showed that the highest production of Chlorophylls a and b are 8.20±0.008 and 3.85±0.06 μg/mg, respectively, which is produced by the sample grown with DUM medium at 10% salinity. Also, the highest amount of carotenoids was 1.79±0.30 μg/mg which was produced by the sample grown in culture medium f/2 with a salinity concentration of 30% under stress. The highest cell growth was 7808333±52041/6 cells/ml at 10% salinity in Gillard culture medium. The results of this study showed that Dunaliella salina algae is a good source of carotenoids when exposed to salinity stress.

Organisms Exposure to multiple contaminants in the environment can have different effects on them than when exposed to only one pollutant. Investigation of the impacts of nano titaniumdioxide and microplastic, on Nile tilapia was the aim of this study. 270 fish (average weight of 23.5±0.6 g) in factorial design (including concentrations of 0, 1 and 5 mg/l nanotitanium and concentrations of 0.5 0 and 1mg/l microplastic) were treated for 30 days in triplicate. The results indicated that the amount of protein in all groups showed a significant decrease compare with control (P<0.05). The amount of albumin and globulin in all groups showed a decrease that was not significant in the microplastic groups alone (P>0.05). Creatinine phosphokinase (CPK) and alanine aminotransferase (ALT) activities as well as triglyceride levels showed a significant increase in all groups except the microplastic group alone (P<0.05). Gammaglutamyl transferase (GGT) activity in all groups showed a significant increase compared to controls (P<0.05). Lactate dehydrogenase (LDH) activity and glucose levels showed a significant increase only in the groups exposed to pollutants (P<0.05) and cholesterol levels did not show a significant change in any of the groups (P>0.05). In general, the results of the recent study showed that the combined groups had more effects on fish. Also, in comparison with the effects of the two pollutants, titanium dioxide had more effects than microplastics and caused more changes in blood parameters.

Selenium is an important trace element for maintaining the fish health. This study aimed to investigate the effect of sodium selenite on survival, growth and some hematological factors relating to the red blood cells of Siberian sturgeon. Three hundred Siberian sturgeon with initial mean weight 10.0±0.5g were randomly distributed in five treatments with three replications and fed with different levels of sodium selenite including zero (control), 0.2, 0.4, 0.8 and 1.6 mg sodium selenite for eight weeks. The results showed that the sodium selenite supplementation significantly increased the final weight and daily growth coefficient of fish with the maximum values of 25.63±0.68 g and 1.22±0.07% d-1 in fish fed with 1.6 mg kg-1 sodium selenite (P<0.05). The feed conversion ratio was significantly decreased after eight weeks feeding with sodium selenite with minimum of 1.79±0.10 in fish fed with 1.6 mg kg-1 sodium selenite (P<0.05). furthermore, equal to or more than 0.8 mg kg-1 supplementation of sodium selenite significantly enhanced the hemoglobin content, hematocrit percentage, and red blood cells count compared to the control (P<0.05). In conclusion, findings of the present study illustrated that 0.4mg kg-1 supplementation of sodium selenite is the best level for maximizing the growth of Siberian sturgeon, while 0.8mg kg-1 sodium selenite supplementation provides the best response in the synthesis of blood cells.

The significant development of nanotechnology and the widespread use of nanomaterials in various industrial fields make it necessary to investigate their destructive effects on biological systems. Therefore, in the use of nanoparticles, attention should be paid to their toxicity. This research was conducted with the aim of investigating the ecophysiological responses of common carp in exposure to nanoplastic-polystyrene as a widely used polymer. A total of 84 specimens of common carp with an average weight of 30±1.5 g, were examined in 4 food treatments (control with commercial food and treatments with diet containing 0.1, 0.5, 1 ml nano-polystyrene emulsion). At the end of the 28 days test period, serum and mucus samples were collected. The results showed, different concentrations of polystyrene nanoplastics had no significant effect on total blood serum protein indices (P>0.05). But the amount of glucose in the concentration of 1 ml (the highest concentration) increased significantly compared to the control group (P<0.05). The experimental treatments caused a significant increase in the amount of soluble mucus protein (P<0.05). Also, experimental treatments caused a significant increase and decrease of ALT and AST in blood serum, respectively (P<0.05). Generally, the results showed that polystyrene nano-plastic increases stress and adverse physiological responses in common carp and these harmful effects are more evident in higher concentrations.

Oceans and seas cover more than 70% of the Earth. They are habitat to many micro and macro organisms those have the ability to produce different bioactive compounds with different applications for obviating human needs. Many pigments, especially phycocyanins, are among bioactive compounds could be extracted from aquatic organisms. Phycocyanin is a protein from the family of phycobiliproteins, which is characterized by its blue color and antioxidant properties. This protein is one of the main pigments in cyanobacteria and many seaweed, including red algae. The antioxidant properties of this pigment make it a good choice for using as a food additive. In addition, phycocyanin is widely used in many sectors such as cosmetics as well as medicine. There are several ways to extract phycocyanin, each of them has advantages and disadvantages. The present study tries to introduce and review phycocyanin and its structure as well as different extraction methods and the effect of factors on this process.

The aim of this study was to investigate the effect of coating nano chitosan with aqueous and alcoholic extracts of Menthe piperata on the quality of Oncorhynchus mykiss fillets so that aqueous and alcoholic extracts of 3 and 5% with a 2% solution of nano chitosan by immersion were placed on the surface of the samples and investigating pH changes, measuring total volatile nitrogen (TVN), thiobarbituric acid (TBA) and free radicals using the 2,2-diphenyl-1-picrylhydrazide (DPPH) test and sensory evaluation was performed by 5-point hedonic method during the first, third and sixth days of storage and the data were statistically analyzed. The results showed that the highest pH level on the third day and in the treatment containing alcoholic extract is 3% and the lowest pH level is on the sixth day. The TBA level of rainbow trout fillets in this study in all treatments was approximately 0.037±0.002. The best result was obtained in DPPH antioxidant activity test for treatment containing 3% aqueous extract of mint on the third day and the highest result was obtained in TVN measurement of a sample containing 2% nanocytosan solution on the third day.

Hexaflumuron is a pesticide used in farms to control insects and has been introduced as a new and effective insecticide to control rice stemborer. This study investigated lethal range concentration and median lethal concentrations of hexaflumuron in common carp (Cyprinus carpio) for the first time. For this purpose, the fishes in 6 treatments received concentrations of 0, 1.25, 2.5, 5, 10 and 25 mg/l hexaflumuron to determine the lethal range concentration and fish mortality was recorded in each treatment at 24, 48, 72 and 96 hours. Then, to determine the median lethal concentration the fishes received 0, 6, 7, 8 and, 9 mg/l hexaflumuron in 5 treatments with 3 replications and the fish mortality was recorded at 24, 48, 72 and 96 hours. The data obtained from the median lethal concentration were analyzed by probit statistical analysis and the ​​(LC5-95), No Observed Effect Concentration (NOEC) and Lowest Observed Effect Concentration (LOEC) were calculated. In this study, the median lethal concentrations of hexaflumuron at 24, 48, 72 and 96 hours were obtained 9.925, 8.395, 8.075, and 7.428 mg/l respectively. Also, NOEC and LOEC were calculated as 0.7428 and 28.42 mg/l. Behavioral and physical symptoms such as lethargy, hyperemia at the base of the fins, red eyes, very slow movements and swimming, vertical swimming, lying on the floor and finally death were observed in fishes. The results of this study showed that hexaflumuron has a moderate degree of toxicity for common carp and fish mortality increases following increasing concentration and exposure to hexaflumuron consumption.

Understanding the optimal habitat of species, especially closely related species, can help in their better management and protection. For this purpose, in the present study, the response of two sympatric species, Garra rufa and Garra gymnothorax, to some environmental variables and the differences between them were analyzed. In this regard, the effect of six habitat variables including the width (m) and depth (cm) of the river, water current velocity (ms-1), altitude (m), temperature (°C) and substrate index evaluated on the Habitat Suitability Criteria (HSC) pattern in 27 study reach, almost in the entire distribution range of these two species. The results showed that G. rufa lives in rivers with width <40 m, depth <45 cm, temperature >22 °C, substrate index 3.5 - 6.5, and depending on the conditions, water current velocity less than 0.45 or more than 1.2 ms-1, which are located at an altitude between 600 and 1000 m, while G. gymnothorax prefere habitats with width <10 m, depth <150 cm, temperature >24 °C, substrate index >4.5, water current velocity <1.05 ms-1 located at an altitude >400 m. The analysis shows that the G. gymnothorax has a smaller range of favorability than G. rufa for all six habitat variables studied, which it somehow indicates its narrower ecological niche and the greater vulnerability of this species to changing environmental conditions. The wider distribution of G. rufa may contribute to the ability to maintain larger populations of this species. This wider presence of the species not only helps to facilitate autecology processes but also increases the probability of survival in case of local environmental disturbances. The results of this study can help in determining the protection priorities for both species.

The increase of heavy metals disturbs the aquatic ecosystems by affecting the physiological, biochemical parameters and cells of the aquatic organism and causes a decrease in the immune function of fishes. The aim of this study was to determine toxic effects of silver sulfate toxicity on some blood indices of Nile tilapia fish (Oreochromis niloticus) fed with different levels of oyster mushroom (Pleurotus ostreatus) prebiotic. 120 Nile tilapia fry were fed for 6 weeks in 4 treatments with 0, 0.05, 0.1 and 0.2% of prebiotics Oyster mushrooms. At the end of feeding period, the experimental samples were exposed to silver sulfate for 14 days, and sampling was done at two times (at the end of the feeding period, at the end of the toxicity exposure) and hematological indices were measured. The results showed prebiotic alone had no significant effect on RBC, MCV, hematocrit and hemoglobin (P<0.05). However, the amount of white blood cells, MCH and MCHC significantly increased in the treatments fed with prebiotic 0.2 and exposure. In general, Oyster mushroom powder stimulated the non-specific immunity of tilapia and also reduced the destructive effects caused by silver sulfate on blood indices. In general, the amount of 0.1 and 0.2% oyster mushroom in the exposed treatments was able to improve the normal blood indices of Nile tilapia.