جستجوی مقالات مرتبط با کلیدواژه « ماهی » در نشریات گروه « شیلات »

The present research was conducted to collect and weigh the criteria affecting the desirability of fish and to provide a coherent and citation ranking for commercial marine fish in Khuzestan province. Semi-structured Delphi interviews with 15 experts were used to identify the criteria. The criteria were prioritized and the sub-criteria were screened using the analytic hierarchy process (AHP) method. A researcher-made questionnaire was used to rank the desirability of fish for consumers and the validity and reliability of the questionnaire were confirmed by conventional methods. Expert Choice and SPSS statistical softwares were used to analyze the data extracted from 181 completed questionnaires. Criteria such as taste and palatability (local weight = 0.209), cooking quality (0.165), thorn density and hardness (0.165), discards ratio (0.153), and price (0.114) are the most striking desirable factors of marine fish in Khuzestan is from the point of view of experts. Fish species including four-finger threadfin (Eleutheronema tetradactylum) (overall weight = 0.379), tiger tooth croaker (Otolithes ruber) (0.368), Sobaity seabream (Sparidentex hasta) (0.364), orange-spotted grouper (Epinephelus coioides) (0.362), silver pomfret (Pampus argenteus) (0.360), Southern meager (Argyrosomus hololepidotus) (0.353), gray sweetlips (Diagramma pictum) (0.353), spangled emperor (Lethrinus nebulosus) (0.351), John’s snapper (Lutjanus johnii) (0.351), and narrow-barred mackerel (Scomberomorus commerson) (0.350) were known as the best options in terms of cooking, preparation, and pre-preparation criteria, respectively, which are more desirable to consumers. The findings of this study can be beneficial for the organizations relevant in the distribution and trade of aquatic animals, such as the Iran Fisheries Organization and it is hoped that the results will be fruitful for production, economic prosperity, and the fishing road map in line with the regulation of domestic markets.

The present research was conducted on Red fish (Carassius auratus, Linnaeus, 1758) in “Gilan Agricultural and Natural Resources Research Center” during Feb 2023-July 2023. In order to prepare a 20% olive leaf extract ointment, 20 g of olive leaf extract was mixed with 100 g of Oserin emulsifier. A total of 30 goldfish weighing 30-25 g were placed in two aquaria of the control and treatment groups with a volume of 1x1x2, m3 of water (25o C , pH= 7/2) with proper aeration and nutritional conditions. After creating wounds on the skin of fish in the control group, no treatment was given, but in the treatment group, 20% olive leaf extract ointment was used on the wounds once per day and continued for 30 days. The healing process of the wounds was measured using calipers at interval days of 5, 10, 15, 20, 25 and 30. The results showed that within 5-10 days after using the extract ointment on fish wounds in the treatment group, the healing process was almost 3 times faster than that of the fish in the control group (p<0/05). After creating a wound in the interval of 15 to 20 days, the process of wound healing and recovery among the fish in treatment group was much faster and the average fish recovery in treatment group was 7 times higher than the wound healing in the control group (p<0/05).

When fish is mechanically processed on a commercial scale, usually between 45 and 55% of its weight is discarded as waste. This amount of waste from aquatic processing contains a large number of nutrients, including protein with high nutritional quality, which, despite its need, is not properly used. In order to optimally use this category of materials and also optimally use underutilization fish, several technologies including the pH shift method were taken into consideration. This method, which is based on the dissolution of the raw material in acid and base (alkali), consists of two stages. In the first stage, the pH of the raw material is reduced or increased by using the corresponding acid or base. This causes the muscle proteins to be charged together and then dissolve in the aqueous medium, and the second stage includes the precipitation of the proteins up to their isoelectric point. The protein obtained from this technique has higher nutritional and functional properties than other conventional techniques for producing protein concentrates such as surimi. This article intends to describe the principles of the pH shift process and the recovery of concentrated protein in this way, the advantages and disadvantages of both acid and alkaline methods and its comparison with the conventional (surimi) processing method, which ultimately the nutritional and functional properties of this process. It is discussed in detail.

In the present study, changes in the quality indices and shelf life of fresh fillets of narrow-barred Spanish mackerel (Scomberomorus commerson) and Javelin grunter (Pomadasys kaakan) were investigated over a 12-day storage period in the refrigerator using sensory, chemical (pH, TVB-N, PV, TBARS), and microbiological (mesophilic and psychrotrophic bacterial counts) indices. The sensory scores of both fish fillets reached less than 4 (the acceptable limit for consumer acceptance) on the sixth and eighth days of storage, respectively. The mesophilic and psychrotrophic bacterial counts in the fillets of both fish increased with an increase in storage days, although the rate of increase was different between the two groups, and psychrotrophic bacteria increased to a greater extent with an increase in storage days. The pH of the fresh mackerel and grunter fillets decreased from 6.52 and 6.24, respectively, at the beginning of the storage period to 7.49 and 7.25, respectively, on the final day of storage. The TVB-N level in both fish increased with an increase in storage days and reached 28.36 mg N/100g in mackerel and 36.25 mg N/100g in grunter on the twelfth day of storage. The lipid oxidation indices, namely PV and TBARS, in the fillets of both fish were significantly higher at the end of the storage period than at the beginning. The results of sensory, microbiological, and chemical indices showed that the maximum shelf life of narrow-barred Spanish mackerel and Javelin grunter fillets is 6 and 8 days, respectively.

Microbiological control of food is important to prevent food poisoning in humans. Pathogenic microorganisms are gram-positive or gram-negative pathogens found in food that cause gastroenteritis. The purpose of this study is to investigate the amount of Listeria monocytogenes and Salmonella in fish, shrimp and eggs presented in Shahrekord city. In this study, 300 samples, including 100 fish samples, 100 shrimp samples, and 100 egg samples, were randomly collected from retail stores in Shahrekord city and transferred to the specialized food hygiene laboratory of Shahrekord Islamic Azad University. The samples were enriched in Listeria enrichment culture medium for 48 hours and then on the selected culture medium and the suspected Listeria isolates from Palcam agar culture medium were counted after biochemical confirmation tests and for confirmation Salmonella was used from SS agar, BS agar and then TSI and LIA culture media. Research The results showed that 2 out of 100 fish samples (2 percent), 4 out of 100 shrimp samples (4 percent), and 5 out of 100 egg samples (5 percent) were contaminated. It was Listeria monocytogenes. The amount of Salmonella contamination for fish, shrimp and eggs was 9, 11 and 18 respectively. Due to the prevalence of Listeria, it is recommended to avoid consumption of undercooked seafood by at-risk populations. Strict implementation of sanitary conditions of food contact surfaces and handling areas, and good personal hygiene practices should reduce possible contamination of seafood products by L. monocytogenes.

The effects of dietary aflatoxin B1 (AFB1) and zearalenone (ZEA) co-contamination on goldfish, Carassius auratus, was investigated. Total of 540 C. auratus fingerlings with an average body weight of 6.25±0.12g were randomly distributed in nine different experimental groups with 3 replicates comprised of three dietary levels of AFB1 (0, 50 and 100ppb) and ZEA (0, 500 and 1000ppb). Fish were fed with the experimental diets for 60 days. Then growth and nutritional indicate and pathology of gill and intestinal tissue were investigated. The results showed that dietary AFB1 and/or ZEA contamination depressed the growth performance, and nutritional indices of the experimental groups; the highest and lowest WG, final body weight, TGC and DGC were belonged to control group and AFB50ZEA1000, respectively (P<0.05). Although the nutritional indices, including PER, PPV and LER, were not significantly different among the experimental groups (P>0.05), the fish fed the diet containing 500 ppb ZEA had the lowest value of LPV (P<0.05). The highest intestine tissue inflammation (4.0±0.75) and necrosis (4.0±0.75) scores were observed in AFB100ZEA500 group (P>0.05). Also, the simultaneous presence of AFB1 and ZEA in the diet increased the severity of the gill tissue damage, including hyperplasia, congestion, hemorrhage, and lamellar fusion in almost all treatments containing AFB1 and ZEA (P<0.05). The results revealed that dietary co-contamination of AFB1 and ZEA could negatively affect fish performance at concentration even lower than those indicated in the literature implying that the safe feed mycotoxin thresholds would be revised in terms of fish welfare and performance.

According to the official reports of the Ministry of Health, Treatment and Medical Education, the corona virus or covid-19 was seen in our country (Iran) from the last months of 2018 and quickly turned into an epidemic. The entry of this virus into the country not only involved the country's health system and caused illness and death of many compatriots, but also had a significant impact on the country's economy in the production and trade sectors. Global reports indicate the negative impact of Covid-19 on the fisheries industry, the same as activities of aquatic processing industries in different countries. In this article, the impact of Covid-19 on the country's aquatic processing industry investigated. In order to conduct this research, a questionnaire containing 31 questions on important topics such as the effect of Covid-19 on the volume and price of raw materials, sales volume, type of product, income, labor forces, changes in the marketing method of processed products and other factors were gathered and subjected to the processing. A total of 56 completed answer sheets were received from the processing centers. The results of the analysis of the response letters showed that during the Corona era, 60% of the respondents confirmed a decrease in the supply of raw materials for aquatic products, 72.2% with an increase in the price of raw materials, 67.9% with a decrease in the volume of production, 80% with an increase in the finished product price, 80.8% with decrease in the volume of domestic sales, 81.5% were faced a decrease in the number of customers. Also, 75% of farmers' responses have reported a decrease in the number of seasonal employees during the Corona era. In terms of product exports, 84% of the respondents said a decrease in the volume of exports.

Number of attempts has been made to cryopreserve fish and shellfish gametes. Success has been achieved to establish only sperm banks in case of some commercially important fish. In shellfish, also particularly in shrimps, though the sperm cryopreservation was successful; no attempts were made to develop sperm banks. As far as cryopreservation of egg and embryos of fish and shellfish is concerned, less research efforts were made with limited success. Number of reasons have been given for the failure of egg/embryo cryopreservation and the main barriers speculated are low membrane permeability in the eggs, the large yolk mass of the oocyte, and the presence of compartments in early developing embryos. These factors result in ice crystal formation during the freezing process. In addition, the oocytes and embryos are prone to chilling injuries unrelated to ice crystal damage. There are number of other problems reported by several researchers in the egg/embryo cryobanking protocols which are elaborately discussed in the present paper. There is an urgent need to develop a viable cryobanking technology for fish egg/embryos to enhance fish production in captive condition. Attempts to cryopreserve larvae of aquatic animals are another challenge occurring in the recent past. The aim of the present review is to collect comprehensive information on the efforts so far made on fish and shellfish egg and embryo cryobanking; and to assess the challenges in the development of viable technology and plan for future research for making this technology viable and cost effective.

The extensive use of di-ethyl phthalate (DEP) as a plasticizer in plastic products, is a major threat to organisms as it leaches out easily from the plastic matrix into the environment. In this study, we evaluated the hepatotoxicity in goldfish (Carassius auratus) upon treatment with DEP. The 96 hr acute DEP LC50 value was determined as > 4 mg/L, using probit analysis. Three sub-lethal concentrations, 1/5th, 1/10th & 1/20th of DEP LC50 were used for 7 and 14 days. Blood and liver samples were taken out, following liver perfusion with saline, homogenates were made. In this study, the content of lipid peroxidation (LPO/MDA) as a marker for membrane disorders, content of carbonylated proteins (CP), and the levels of ALT and AST (as hepatic necrosis markers) were increased in the liver of DEP-treated fish. Meanwhile, the total antioxidant capacity (TAC) was found to be lowered in liver homogentes. In brief, DEP caused hepatotoxicity in fish through induction of oxidative stress followed by cell membrane instability.

Heavy metals can enter to the aquatic animal's body through dietary or water sources and exert their harmful effects. This study was conducted to compare the toxicity of lead in common carp via diet and water borne conditions. Total number of 135 fish (average weight of 50±10 g) was divided into three groups (each with triplicate) including control, water borne (1 mg/L) and diet borne (1 mg/kg dry diet) lead. Experiment was executed during 21 days and sampling was done at 7, 14 and 21 days after trial initiation. Blood biochemical factors including total protein, albumin, globulin, creatinine, glucose, cholesterol, alkaline phosphatase (ALP), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) were measured in mentioned sampling times. Results showed that lead exposure led to negative effects on blood biochemistry in both groups, but in the case of glucose, LDH and ALP, significant changes were observed between diet and waterborne lead. It may conclud that the diet borne had more toxic effects than waterborne lead and therefore, lead had more potential toxicity through diet in common carp.

Concerns about the negative effects of microplastics on human health have led to increasing attention to the occurrence of microplastics in the aquatic environments. Recent studies have focus from the marine environment to inland waters, particularly the spatio-temporal distribution of microplastics in rivers. Qarasu basin, leading to Gorgan Bay, is the site of many permanent rivers and the levels of microplastic pollution in those rivers are unknown. This study was conducted along 8 different rivers in 2020. Some 9 fish species were identified and the presence of microplastics was confirmed in 87% of fish. The prevalence of microplastic particles among species were Chelon spp.> Carassius gibelio> Gambusia holbrooki> Rutilus rutilus> Neogobius melanostomus> Cyprinus carpio = Vimba persa> Rutilus caspicus> Barbus cyri. The highest type, color and size of fish microplastics were fiber, black, 0.5-0.1mm, respectively. In conclusion the rivers of Qarasu basin have been polluted by microplastics not only in developed areas with intense human activity but also in upstream areas, which can be considered as a source of pollution in Gorgan bay.

Organisms living in frigid environments have evolved different mechanisms to deal with cold air. The emergence of the antifreeze protein gene is one of the most important mechanisms. Antifreeze proteins have critical functional properties for organisms to survive in cold environments. These proteins prevent freezing damage in living organisms such as fish by binding to ice crystals. The variety of species that contain this type of protein and the diversity of the proteins has resulted in the development of a wide range of antifreeze proteins of varying sizes and functions, which has piqued the interest of a variety of companies. Although the development of antifreeze proteins technology is in its infancy, it could have great potential for future performance. Meanwhile, marine resources provide humanity with a unique potential to create such valuable molecules due to their breadth and climatic variability. With this approach, the present study aims to study and introduce antifreeze proteins derived from fish to provide a comprehensive knowledge of the types of antifreeze proteins in them and their potential applications.

Fars Province in southern Iran includes the main basins of the Kor River, Maharloo Lake, Persis, Hormoz and Karun. The Kor River Basin, as an inland basin, is an important part of the freshwater Ichthyodiversity. Cheshmeh Gomban (Gomban spring) and its surrounding wetlands are important water sources of this basin and water bodies of the Tashk and Bakhtegan Lakes. In this study, the ichthyodiversity in the Cheshmeh Gomban wetlands and their conservation threats (human and non-human) in 2010, 2017 and 2018 have been investigated. In the field work of the previous years, 5 fish species including 4 endemic species and an exotic species belonging to 5 genera and 3 families (Acanthobrama persidis, Alburnoides qanati, Aphanius sophiae, Capoeta saadii, Gambusia holbrooki) have been identified from the Cheshmeh Gomban wetlands, which in the recent study, this number was reduced to two species. Recent prolonged droughts, uncontrolled abstraction of water from wetlands by various methods and the presence of non-native species are the main threats to the habitats and populations of fish and other biota in Fars Province. Immediate conservation measures are necessary to rehabilitate the wetlands.

Nowadays, due to the significant increase in the number of referrals of sick fish to aquatic animal specialists and clinics and the consequent increase in their contact with fish, the importance of the need to obtain the necessary knowledge and accurate and comprehensive information on how to prevent zoonosis disease's transmission from fish to human, is understood increasingly not only for aquatic professionals but also for all people involved in the field of aquaculture. One of the most well-known zoonose diseases among fish and humans, which is transmitted to humans through direct contact, is a disease caused by the invasion of mycobacteria called fish mycobacteriosis or tuberculosis. Mycobacteria are a group of aerobic, non-motile bacilli that are acid-alcohol resistant and grow slowly. They can cause prominent granulomatous nodules and extensive losses in fish. Exposure of human skin abrasions to sources contaminated with Mycobacteria can lead to the formation of different types of tuberculosis in humans. The clinical manifestation of this disease is often in the form of not so painful nodules with skin ulcers and scars in humans. A variety of methods such as culture, PCR, and preparation of histopathological sections can be used to identify and diagnose Mycobacteriosis. This study provided comprehensive information on the introduction, clinical signs, necropsy symptoms, pathological symptoms, transmission, diagnosis, control, treatment, and health considerations associated with fish Mycobacteriosis.

The use of pesticides has always been associated with environmental concerns. Vista is a new and widely used pesticide in rice fields for blast disease. The present study investigated the lethal range and median lethal concentration of Vista fungicide in Ctenopharyngodon idella, for the first time. In this study, to determine the lethal range fish were first exposed to the concentrations of 0,10, 25, 50, 100, 250 and 500 mg per liter of Vista, and fish mortality were recorded in each group for 24, 48, 72 and 96 hours. Then, in order to determine median lethal concentration, fishes in 5 groups received concentrations of 0, 30, 35, 40 and 45 mg per liter Vista with three replication, and the number of fish mortality was recorded at 24, 48, 72 and 96 hours. The results were evaluated by probit statistical analysis. In this study, the median lethal concentration of Vista were 60.5, 40.1, 34.58 and 31.28 mg per liter at 24, 48, 72 and 96 hours, respectively. The Maximum Allowable Toxicant Concentration of Vista fungicide was 3.128 mg per liter, and its Lowest Observed Effect Concentration was estimated to be 28.42 mg per liter. The results of this study showed that the lethal concentration of Vista fungicide decreased with increasing test time, so that as the test time increased, a lower concentration of Vista fungicide caused fish mortality.

The aim of this study was to investigate the rate of changes in liver enzymes in the plasma of Epinephelus stoliczkae under the exposure of different concentrations of potassium dichromate during 21days in vitro.

200 pieces of Epinephelus stoliczkae with average total length 29.6±2.2cm and average total weight389.5±92.4g were caught from the Oman Sea. Three treatments of 3.6, 7.31 and 14.6mg/L chromium(three replications and one control) were selected to sub-lethal toxicity test. The fish were exposed to chromium for 21 days and at 0.5, 1, 7, 14 and 21 days after the start of the experiment to measure the levels of liver enzymes aspartate aminotransferase(AST), alanine aminotransferase(ALT) and alkaline Phosphatase(ALP), blood was obtained from tail stems of fish. The amount of enzymes was measured using photometric method and values ​​were expressed inU/L.

The highest and lowest levels of liver enzymes in Epinephelus stoliczkae were: aspartate aminotransferase=198.16±6.21-298±10.28, alanine aminotransferase=38±2.56-81±2.19, alkanin phosphatase=118±4.21-177±2.7U/L.Over time, the amount of liver enzymes in different treatments increased compared to the control group and showed a statistically significant difference(P<0.05).For all three liver enzymes, the highest amount was recorded in the third treatment and 21 day and the lowest in the first treatment and time of 0.5 days.

In this experiment,liver enzymes increased in response to an increase of chromium concentration and duration of exposure, which could be due to damage the liver cells and release of liver enzymes into the plasma.In general, liver enzymes can be used as biomarkers of pollution in natural environments.

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 Gobiidae are one of the largest families of fish in the world. This study aimed to investigate the morphometric characteristics of the specimens belong to three species from Gobiidae family, i.e. Acentrogobius dayi, Bathygobius meggitti and Istigobius ornatus from Makran coast, South-East of Iran. A total of 56 specimens from three Tis, Lipar and Darya-Bozorg stations during the spring and summer of 2018 were captured and transplanted to the laboratory. 36 morphological variables were analysed (including univariate and multivariate), using SPSS and PAST software. The results showed that there was a significant difference between the studied species, mainly in head and pectoral fins. But other characters were not significantly different. The results of cluster analysis showed that B. meggitti was considerably different from the others. This study also demonstrait significant intra-specific differences regarding I.ornatus species. These differences moreover than the head and pelvic fin , were seen in the tail fin. In A. dayi species, intra-specific differences, same as what observed at inter-specific level, were mainly in the head and pelvic fin’ part. A multivariate analysis of  the characters and pairwise comparision of the populations of two species I. ornatus and A. dayi showed that the populations of Lipar and Darya-Bozorg stations in both species are more similar than others. An advanced molecular study as a complementary study can help to clarify species diversity and taxonomy of these poorly known family.

Fish sampling was conducted to evaluate the species diversity of fish in 4 stations in Sanandaj Azad dam ecosystem seasonally from summer of 2017 to spring of 2018. A total of 1057 fish were caught in 12 species, of which more than 80% were caught in the lake behind the dam. The Cyprinidae family had 11 species with the most species diversity and only Sasanidus kermanshahensis belonged to the Noemachilidae family. There was no significant difference between Shannon species diversity in the lake behind the dam (with a mean of 1.11 ± 0.32) and Komaci River (P> 0.05), and in summer with other seasons there was a significant difference (P <0.05). The size and weight of the population living in the lake habitat behind the dam were significantly higher than the population living in the river habitat (P <0.05). Among the identified fish species, 5 species Carrasius auratus, Cyprinus carpio, Hemiculter leucisculus, Hypophthalmicthys molitrix and Pseudorasbora parva are exotic species. Among the influences of exotic fish is its competition with native fish for food, and this will have a significant impact on the species diversity of the fish, population dynamics and fish populations. Also Sasanidus kermanshahensis is an endemic species for Iran, which is very important for protection. Considering the importance of endemic species and the presence of a considerable number of exotic fish species in the Azad dam ecosystem, the results of this study are of considerable importance.

The length-weight and some length- length relationships of six fish species, including Lutjanus malabaricus, Acanthopagrus latus, L. johnii, Rastrelliger kanagurta, Gerres longirostris and Sillago sihama from the Persian Gulf were studied. The specimens were collected from landing centers and their morphometics, including total length (TL), fork length (FL), standard length (SL), body depth (BD), and caudal fin height (FH) measured to the nearest mm and weighed to the nearest 0.1 g. All length-weight relationships were significant, with the coefficient of determination (r2) ranging from 0.84 (G. longirostris) to 0.98 (L. malabaricus) (P<0.01). The parameter b ranged from 2.54 (R. Kanagurta) to 2.98 (S. sihama). The results indicated isometric growth in L. malabaricus, A. latus, L. johnii, and S. sihama andnegative allometric growth pattern in G. longirostris and R. kanagurta. The results indicated that the length-length (TL-FL and TL-SL) relationships were highly correlated and significant for all species (P<0.01). The relationship between TL-BD and BD-FH was also significant, except for R. kanagurta (P>0.01).