مجله علمی شیلات ایران
سال سی‌ام شماره 3 (پیاپی 125، امرداد و شهریور 1400)

Pheromones are molecular signals of hormones or their derivatives that affect the same species in the environment outside the body. The effect of ovary extract of psyllium as a pheromone-containing substance (PGF2α) on pheromone induction and the process of final sexual maturation and changes in male sperm indices of this fish have been investigated and compared in different treatments. Male fish with an average weight of 45 ± 200 g were released in 300 liter fiberglass ponds and after adapting the fish to the environment (for 48 hours), the experiments were performed in 5 experimental groups (one control group, one prostate gland control group and 3 groups Treatment) in which each group consisted of 9 adult male fish. Different concentrations of ovarian extract were added to the water in three treatments of 5, 10 and 15 mg / l as a bath. After 24 hours, the fish were anesthetized and fish biometrics was performed by measuring length and weight. After blood sampling, fish gonads were weighed. The results showed that pheromone induction of ovarian extracts and their positive effect on increasing the rate of sperm counts. Gonadosomatic index as well as testosterone levels at 10 and 15 mg / l treatment and prostaglandin treatment (PGF2α) were significantly increased compared to the control (p <0.001). Sperm density and spermatocrit in the treatment of 15 mg / l (T3) had a significant decrease compared to the control, but the indices of sperm motility rate and sperm motility percentage compared to the control did not show a significant difference. Relative sperm volume in all treatments was affected by pheromone extract and a significant increase was observed compared to the control in T3 treatment (p <0.001). Administration of pheromone extract resulted in control of male reproductive fish reproduction in all experimental groups.

The present study was conducted to investigate the effect of different levels of Aphanothece halophytica species of Aphanothecaceae family on the growth process and carcass chemical composition of Artemia urmiana nauplius for 3 weeks. For this purpose, the cysts were hatched identical standard conditions. Then 1200000 Nauplius were used in a completely randomized design with 4 experimental treatments and 3 replications (with 100000 in each replication), including control treatment (1 g yeast per 10,000 Nauplius), and experimental treatments of 100 mL/L microalgae included: treatment 1: ( 22×106 cell/mL microalgae), treatment 2: 16×106 cell/mL microalgae) and treatment 3: (13×106 cell/mL microalgae) in cylindrical-conical (2 liter) plastic containers with a temperature of 28°C and a salinity of 30 g/L. The results at the end of the experiment showed that the highest length was associated in treatments 2 and 3 and the highest weight was related to treatments fed with different microalgae levels. However, there was no significant difference in weight between microalgae-treated treatments (p>0.05). The results showed that at the end of experiment, the highest length in treatments 2 and 3 was observed. The highest weight was shown in treatments fed with different levels of algae. However no significant difference (p>0.05) were observed in among treatments fed with algae (p>0.05). Highest moisture content (91.67±0.54%) and lowest lipid content (3.84±0.04%) in the control treatment, the highest percentage of highest dry matter (11.15±0.15%) and lipid (6.54±0.09%) was observed in treatment 2. The highest percentage of protein was observed in treatment 1 (p>0.05). Overall, the results of this study showed that the use of different levels of A. halophytica microalgae on the length, weight and carcass chemical composition of Artemia naupliis showed a better effect compared to control treatment and the use of treatment 2 is recommended in the diet of A. urmiana nauplius.

In recent years, the use of bacteria is growing to research into the reduction of chemical pollutants. However, no information has been reported on the protective effect of these bacteria on living organisms, including Artemia. Thus, the effect of probiotic Pediococcus acidilactici on reduction of diazinon pesticide toxicity in Artemia franciscana was investigated. In the first, the lethal dose of diazinon toxin was determined on Artemia nauplii. Then five treatments of different probiotic concentrations (3.75×106, 7.5×106, 11.25×106 and 15×106 CFUmL-1) were used to evaluate the reducing effect of the diazinon in the culture media of Artemia nauplii. For to this, five concentrations of 20 to 60 mgL-1 were used to determine the 24h-LC50 toxicant concentration in A. francicana, which at the lowest concentration, the mortality rate was more than 50% over a 24-hour period. In the second experiment, the concentrations of 12 to 18 mgL-1 diazinon were used. Based on the results, the 24h-LC50 lethal concentration was calculated as 12 mgL-1. The amount of diazinon in different concentrations of probiotic bacteria was calculated by gas chromatography. Toxin removal was observed at 82% at the lowest bacterial concentration (7.5×106 CFUmL-1) and 95% at the highest density (22.5×106 CFUmL-1). Simultaneous addition of bacteria and diazinon significantly reduced Artemia mortality compared to the control treatment (p<0.05). However, in different probiotic treatments, bacterial concentrations showed no significant difference in Atremia mortality (p>0.05). The results of this study indicated that the probiotic P. acidilactici has a significant effect on reducing the toxicity of diazinon as an organophosphorus toxin. The results also showed that the simultaneous presence of diazinon and bacteria on the rate of Artemia mortality indicates the elimination and inactivation of the toxin by the bacteria.

This study was designed to determine the influence of both free and nanoencapsulated quercetin on fatty acid profile of zebrafish (Danio rerio) muscle and eggs. To this end, a total of 120 fish were divided into 4 experimental groups and fed with following diets: control, without additive; chitosan, 400 mg nanochitosan per kg diet; Qu, 400 mg free quercetin per kg diet; Qu-chi, 400 mg nanoencapsulated quercetin per kg diet. To assess fatty acid profile, the muscle and eggs was dissected after feeding trial. No significant difference was recorded for fatty acid profile of muscle and eggs in the chitosan group. Considering muscle tissue, however, the fish treated with free quercetin significantly elevated the levels of ARA, DHA, ∑HUFA, and ∑n-3 when compared to control group, whereas the fish received nanoencapsulated quercetin showed a significant increase in DHA, EPA, ARA, ∑n-3, and ∑HUFA levels in comparison to the other groups. Concerning eggs fatty acids, the fish received free quercetin increased the percentage of EPA, yet the animals treated with nanoencapsulated quercetin did the levels of EPA, DHA, ∑HUFA, n3/n6, and ∑n-3. Together, quercetin could enhance the fatty acid profile of zebrafish muscle and eggs, and nanoencapsulation process could enhance the performance of free quercetin.

This investigation has done to determinate of growth pattern and growth parameters of Austruca sindensis on northern coast of Qeshm Island during January 2017 to December 2018 monthly. Individuals have collected by digging burrow and then fixed in formalin solution 10%. Overall 841 samples collected which included 464 of male crabs (carapace width mean of 12.39±2.17 mm) and 377 of female crabs (carapace width mean of 11.42±1.53 mm). All of morphometric parameters were significantly higher in female than male crabs (p<0.05), except carapace length. The exponential value (b) estimated was obtained 2.78 for male crabs and 2.71 for female crabs. (p>0.05) which indicated positive and negative allometric growth for male and female crabs respectively. In this study, asymptotic carapace width (CW∞), initial hypothetical size (t0) maximum life span estimated 25 mm, -0.11, 2.3 year for male and 20 mm, -0.10, 1.9 year for female. Also, growth rate (k) and mortality of female were high in comparison to male crabs. Variations in the condition factor were similar for both sexes, and correlated with temperature.

The aim of this study was to study the archeology, breeding and review of fish in the Persian Gulf, Strait of Hormozand the Gulf of Oman, and to obtain new information on the final list of fish species in this sea basin with emphasis on the Iranian waters. Accordingly, cataloging the scientific and approved names of families and species based on sources from 1940- 2021, and classifications at the family, genus and species taxon, and coding of the International Zoological Standard (ICZN) was done.The result was showed that final list of approved species is 974 species (169 families), of which 26 families with 93 species of chondrichthyes (12 families with 50 species of sharks, and 14 families with 43 species of rays) and 143 families with 881 species it is related to osteichthyes. Of the chondrichthyes, carcharhinidae (26) of the sharks and Dasyatidae (13) of the rays have the largest families in terms of species diversity. From the group of osteichthyes, 23 families with more than 20 species have the most diversity, of which Gobiidae and Carangide (48), Labride (41), Blenniidae (39), Apogonidae (33), Pomacentridae (32) and Lutjanidae (31), the most family are considered in terms of species diversity. There are also 67 families, including 8 families of chondrichthyes and 59 families of osteichthyes are mono species in the area. The two families Clinidae and Creediidae have also been identified and introduced based on their larval stages specimens in the area.

In this study, the ability of Spirulina platensis microalgae in dairy wastewater treatment and nutrient removal associated with biomass production was evaluated. Therefore, two concentrations of Spirulina platensis (0/05 and 0/1 g/L) were cultured in three dilutions (25, 50, 75%) of dairy wastewater and the efficiency of nutrient removal and biomass production was evaluated with six treatments in three replications. Nutrient and biomass values ​​were measured on every other day. The results showed that both factors of different concentrations of algae and different dilutions of wastewater had an important role in nutrient absorption and biomass production. The highest percentages of nitrate, phosphate, ammonia removal (99/85, 82/60, 99/83%) and maximum amount of biomass (1/690±0/01 g/l) in 25% dilution and concentration of 0/1 g/l microalgae was obtained. In this research, by decreasing percentage of dilution of dairy industry wastewater and increasing amount of nutrients available in microalgae and also by increasing the initial concentration of injectable microalgae in the wastewater, more nutrients were removed, and the nitrate and ammonia levels were almost 100% eliminated and the amount of biomass increased. As a result, according to the results, Spirulina platensis microalgae has a high performance in removing nutrients (nitrate, phosphate, ammonia) from dairy industry wastewater and can be considered for dairy industry wastewater treatment.

Despite the great benefits of aquatic to the health of the society and its good production capacity in Iran, the per capita consumption of this meat is lower compared to the other meats in the household food basket. The present research studied the factors affecting the selection of high- consumption marine fish in Bandar Abbas. The required data including the characteristics of consumed marine fishes, economic and demographic characteristics of households, were collected using a cluster random sample of 384 households in the summer of 1397. High-consumed fishes in the study area were classified into three groups based on their prices and characteristics, which are statistically significant according to the Kruskal-Wallis test. The mixed logit model was used to find the effect of economic and demographic characteristics on the selection of fish species. The results showed that with the increase in the level of education and income, the probability of choosing the first group increases by 8 and 62 percent, respectively. In other words, fishes with easy separable blades and more meat and better taste are selected. However their price is higher compared to the second and third groups. The latter two groups of fishes are consumed more often than the first group as they are cheaper. Given the nutritional value of fish and its role in consumer health, marketing promotional programs can lead the consumers to use the second and third groups of fishes more than the first group.

The aim of the present study was to risk assessment and zoning the unsustainability of shrimp fishery in the shrimp fishing-grounds of the Hormozgan province (Sirik to Toola). Data were collected during two shrimp fishing seasons in 2017 and 2018 (between September and December). The criteria affecting the shrimp unsustainability risks were extracted using international literatures and also conducting some in-depth and semi-structured interviews with the experienced fishermen and knowledgeable researchers. Thereafter, the coefficient of determination was obtained to each criterion by using a quantitative questionnaire. Finally, integration of these criteria was done by fuzzy-neural modeling. Data analysis indicated that 57.35% ±15.6 (±SD) of fishermen are totally satisfied with their job. The maximum value for ecology criteria was 0.56. in Kollahi fishing ground. In Bandar-Abbas fishing-ground, the highest values for fishermen's security threats, satisfaction with existing management status and social conditions of fishing communities' criteria were also computed 0.08, 0.18 and 0.08. The maximum coefficient of determination was belonged to catch volume (with 0.0922) and fishers' livelihood (with 0.409) in Dar-sorkh. The highest unsustainability risk was observed in Bandar Abbas and east of Sirik, while central regions and around of Darsarkh, Toola and Kollahihad the lowest. Ecological criteria were also maximum in the central areas of the province, which is indicating the suitable habitat conditions. The unsustainability risk in Sirik was also due to the low catch rate and the fishermen's livelihood. It sounds that management of the illegal fishing and conservation and expansion of the marine protected areas could helpful to improve sustainability of shrimp fishing in Bandar-Abbas fishing-ground. The fuzzy integrated model obtained in the present study prepared spatial prioritization and determined the criteria affecting on shrimp fishing sustainability in the Hormozgan province, which could more guide the managers to improving fisheries sustainability in the region

A feeding trial was conducted to examine the effects of dietary supplementation of betaine on growth, nutrient utilization, carcass compositions and haematological- biochemical parameters in Salmo caspius fed a plant-protein based diet. 180 fish with average weight of 9.7±0.59 g were fed the plant-protein basal diet, the basal diet with 1.4 & 2.8% betaine supplementation, or a fishmeal-based diet (control) for 11 wk. Weight gain, specific growth rate and protein efficiency ratio were significantly higher in fish fed the betaine-supplemented diet (1.4 & 2.8%) as well as control diet than in fish fed the basal diet. The lowest and highest whole body protein and lipid concentrations were significantly found in the fish fed by basal diet. Based on the results of this study, the levels of liver enzymes were significantly higher in fish fed the betaine-supplemented diet (1.4 & 2.8%) as well as control diet than in fish fed the basal diet. The value of apparent digestibility of crude protein in diet-fed fish a fishmeal-based (control) were significantly higher than fish fed plant-protein basal diet and the basal diet with 1.4% betaine supplementation (p<0.05). Based on the results of this study, could be said that increased levels of 2.8% of betaine is an effective feeding stimulant that can be enhanced the palatability and intake of plant-protein based diets for Salmo caspius, improved growth performance, feed utilization and apparent digestibility coefficient.

The purpose of this study is to investigate the behavior of buyers of fish in western cities of Mazandaran province. For this purpose, 383 questionnaires were designed based on research hypotheses and completed in proportion to the number of households in the cities of Noor, Nowshahr, Chalous, Abbasabad, Tonekabon and Ramsar. To investigate status of the acceptance or rejection of hypotheses a conceptual model of behavior was designed and implemented by LISREL software (Structural equation modeling method). The results of this study showed that 46.12% of the statistical population buys fish three times a year. The first priority of 57.56% of buyers was rainbow trout. The first preference of the majority of respondents (77.45%) to choose the place of purchase was the fish market. The main reason for 84.67% of people not to eat fish as recommended by the World Health Organization was the high price. In this society, only 5.36% of people preferred packaged fish in first priority and most of them (59.71%) chose the model without head and empty stomach (fresh) in the first priority. 25.36% of respondents answered that the main reason for consuming fish is purely nutritional value. In this study, four hypotheses of significant effect of packaging and price on attitude as well as significant effect of availability and time on perceived behavior control were rejected and the rest of the hypotheses (Significant effect of specie, quality and type of supply on attitude, Significant effect of price on behavior control, Significant effect of attitude on the decision to buy, Significant effect of behavior control on decision to buy and final behavior, Significant effect of decision to buy on the final behavior) were confirmed. Based on the effect coefficient values, quality was mentioned the most effective factor on attitude.

The aim of this study was to determine the biodiversity indicators of fish in Dinor River, Kermanshah province. For this purpose, in July 2018, six stations were selected for fish sampling along the Dinor River, with Station 6 upstream and Station 1 downstream. Fish sampling was performed using an electroshocking device. In total, 2543 fish specimens were caught from the Dinor River, belonging to 20 species. In this study, most of the species caught belonged to the family Cyprinidae. Alburnus sellal and Capoeta trutta had the highest and lowest abundance among the studied species, respectively. In the present study, biodiversity indices including Shannon-Wiener, Margalf, and Simpson, species richness, dominance and homogeneity were determined. The results showed that the Shannon-Wiener and Margalf indices increased from the upstream stations (6 and 5) to station 4, but decreased after the fourth station. In relation to the Simpson index, the fourth station showed the highest value of this index, but then fell sharply in the third station. In terms of species richness, stations 6 and 4 had the lowest and highest species richness, respectively. Although Station 4 had the highest level of homogeneity among the studied stations, but after this station, a decrease in homogeneity was observed in the downstream sections, especially Station 3. In this study, the dominance index showed an inverse relationship with homogeneity, so that the dominance value was lowest in station 4 and reached its highest in station 3. Changes in biodiversity indices along the Dinor River can be due to land-use changes in the riparian zone, improper extraction of sand, as well as the entry of pollutants from agricultural, industrial and domestic wastewater into the Dinor River.