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

More than 50 fish species exist in Guilan coast waters and 20 species of them are economic, but there is few data about their fingerlings. This study has been done in Talesh, Anzali, Kiashahr and Chaboksar shores and fish seasonally caught by beach seine with 8 mm mesh size from winter to autumn 2021, and the main purpose was determining fish abundance in Guilan province coasts, too. Results showed 32 fish species belong to 13 families in studied are and Leuciscidae family was the most diversified with 8 species. The study of fish abundance showed dominancy of Chelon saliens, Alburnus chalcoides and Atherina caspia with 42.5%, 18.1% and 11.6% in Talesh shore, A. chalcoides, C. saliens, and A. caspia with 25.1%, 22.1% and 20.8% in Anzali shore, C. saliens, Rutilus frisii and A. chalcoides with 31.8%, 17.4% and 14.8% in Kiashahr shore and C. saliens, A. chalcoides, Neogobius pallasi and chelon auratus with 29.9%, 21.5%, 14.2% and 10.5% in Kiashahr shore, of total count (number), respectively and they were predominant. In general, were abundant fish, the fingerlings to non-adults of sharp-nosed grey mullet (Ch. saliens) and Shemaya (A. chalcoides) in all stations, Caspian silverside (A. caspia) in 2 stations and fingerlings of Golden grey mullet (Ch. auratus) and Kutum (R. frisii), and fingerlings to adults of Caspian sand goby (N. pallasi) in one station, that show a more adaptation of these species to environmental conditions in 4 studied stations. The continuous monitoring of density of small size individual of fish species in southern coasts of Caspian Sea is essential for conservation of their populations.

The current research was conducted in 2021 in 5 stations in order to investigate the quality of water before the operation of Javeh Dam in Kurdistan Province. Sampling of fish and Macrobenthos was done using an electrofishing device and Surber sampler, respectively. A total of 13 fish species were identified, which belonged to 3 families: Cyprinidae, Mastacembelidae and Nemachielidae. Out of the total of 2003 fish caught in all the stations, more than 96.6% belonged to the Cyprinidae family. The highest relative frequency of 32.4% belonged to Capoeta damascina species. In addition, 2 exotic species, Carrasius auratus and Carrasius gibelio had an abundance percentage of 1.4. The diversity of fish species decreased from station 1 (upstream) to stations 2 and 3, which was probably influenced by human activities such as various types of pollution, but in station 5 of It had the maximum amount, which is due to the change in habitat conditions, such as the increase in flow rate and water depth. The results showed that the species diversity of fish had changes in different seasons, so that its minimum was estimated at 0.91 in winter and its maximum at 1.29 in summer. Macrobenthos included 10 families Chironomidae, Lumbriculidae, Simulidae, Baetidae, Hydropsychidae, Erpobdelidae, Glosiphonidae, Gamphidae, :union:idae and Potamidae. The classification of water quality based on the Karr ecological integrity showed that stations 1 and 4 were placed in the good quality class with a numerical value of 40 and 42, respectively, and stations 3 and 5 were placed in the very low and medium water quality classes with a numerical value of 9 and 34, respectively. In this way, it is necessary to manage and organize all sources of point and non-point pollutants in Gheshlagh and Gavehroud tributaries.

Open pollution compounds such as nitrate, nitrite and ammonium acute or semi-acute water poisoning, especially juveniles’ fish create a short-term and long-term depending on the concentration impairs physiological activities and cause of death is unknown. Most affected by the contamination of farmed fish, their immune system is compromised. The main toxic reactions due to the conversion of nitrates in the water carry oxygen to the forms that are not capable of carrying oxygen. Nitrate toxicity on aquatic animals by increasing the concentration and exposure time increases. In contrast, nitrate toxicity may be associated with increasing body size, increase in water salinity, and reduced environmental sustainability. Fresh water animals seem to be more sensitive to nitrate is marine animals. Nitrate concentrations around 10 mg (maximum for drinking water according to Federal America) can have negative effects, at least in the long term exposure, freshwater invertebrates, fish and amphibians influence. Safe area under the concentration of nitrate to protect freshwater animals susceptible to nitrate contamination is recommended. In addition, the maximum level of 2 mg to protect the most sensitive freshwater species would be appropriate. In the case of marine animals, the maximum level of 20 mg is generally acceptable. However, in the early developmental stages of some marine invertebrates that have adapted well to the low nitrate concentration, may be more susceptible to nitrate are sensitive to freshwater invertebrates.

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.

A total of 4292 fish samples were caught. Sampling was carried out at 3 stations monthly, using a beach seine with 20 meter in length and 5 mm mesh size from node to adjacent node. The purpose of this research was to investigate the status of fish in the year of sampling in 1994 and compare it in 2014. A total of 9 families, 16 genera and 20 species were identified. The most species diversity was obtained from the family of Cyprinidae and Gobiidae with 6 and 5 species, respectively. Based on the results, the Shannon index ranged from 0.924 to 1.3622 and the Simpson index ranged from 1.893 to 3.158, the Margalf index ranged from 1.258 to 2.262 and the Pillow index varied from 0.341 to 0.619. This could be due to the ecological conditions of the area, the presence of canals, vegetation and proper water quality. There was a significant difference between the variability indices at different stations (p

This study focused on population structure, species diversity and abundance of the Chitgar Lake fishes in October 2014. Based on the lake location fish samples were collected at 34 stations in water body. In this study , 8 families belonging to 18 species comprised of Cyprinidae (11 species), Cichlidae (one species), Loricariidae (one species), Pangasiidae (one species), Serrasalmidae (one species), Poeciliidea (one species), Salmonidae (one species), and Scaridae (one species) were identified. Among the fishes just one native fish from Capoeta bohsei species observed during the study. The dominant lake fishes were invasive species Hemiculter leucisculus, Alburnus hohenackeri, Carassius auratus, Carassius gibelio and Pseudorasbora parva. The highest abundance of fishes were H. leucisculus 62 % and A. hohenackeri 35 % by Seine net. Furthermore, those were dominant abundance (69 and 12 % respectively) in Gill net method. Finally, in Cast net method A. hohenackeri 38 %, Pseudorasbora parva 21 % and H. leucisculus 17 % were dominated in the shore region. The lowest fishes abundance were P. hypophthalmus and Parrotfish. Overall more than 90 % of the fish population were invasive and alien species. Thus, the presence of invasive fishes and lack of predator fishes in the Chitgar Lake might be reason for increasing of trophic level.

Drying is one of the methods of food preservation with long-term. These processes increase the shelf life and ability for using them, because of taking water. The study had two treatments that include Sphyraena jello and Sphyraena forsteri. The first and second parts were put in the open air and in a plastic sheets respectively, so that the ground was 60 cm distance and allow to dry. Fish were dried so that were put in the open air for 5 days. Second part also were dried for 8 days and then samples were powdered and packaged. Samples were transferred to the laboratory for analysis of protein, fat, ash, moisture, carbohydrates and energy with AOAC standard methods. The results showed that the amount of fat in fish dried Spyraena jello in the open air and the plastic sheets found 5/98.02 and 5/72.22, protein content were 58/31.31 and 61/03.04, ash content found 14/35.35 and 15/01.01, and energetic values found 385/59 and 398/46 kcal respectively. The results also showed that the amount of fat in fish of dried Spyraena Forsteri in the open air and the plastic sheets found 3폽 and 4폽, protein content found 61/90.24 and 61/16.24, ash content found 20/80.0015 and 24/85.0015, and energetic values found 377/50 and 382/84 kcal respectively. We concluded that the open air for fish drying was faster, but in plastic method, fish nutrients, such as fat, ash, moisture and protein, were preserved better.

This study on set-net fishing at the coastal area of Bandar Abbas was conducted from October to April 2012. A totally of 54 setnet operations were recorded, random samplig monthly of 9 setnet from Nakhlenakhoda, Khajehatatta and Suru were conducted. Results showed that a total of 66 species and 54 genus belonged to 45 families of fishes were caught by the set-net in Bandar Abbas coastal area. Nakhlnakhoda were consisted of 39 species, 35 genus and 31 families, Khajehatta, 42 species, 40 genus and 37 families and Suru 34 species, 28 genera and 26 families respectively . Analysis of catch composition were showed that in Nakhlnakhoda Goaf (39.7%), Kalar(10.8%) and crabs (9.5%), in Khajehatta Chacunda gizzard shad (38.5%), Mullets(20.9%) and Sardine(5.1%), and in Suru White sardine( 56.4%),Whipfin silver-biddy (7.1%) and Milk fish (6.4%) were dominated. In order to analyze the economical and social situation of bandarabbas setneters community of interviews and questionnaires were used in the social and econimic conditions of society setneters enrolled 20 person analyzed.In this investigation it has been determined that the estabishment of the oldest fishing setnet about 40 years ago and most recent 12 years of experience.On the other literacy rate of setneters showed that only 30 percent have no education.47 percent of setneters saied that their setnets is hereditaryd,16 percent have purchased their setnets and 37 percent said they have ownership of set nets. according to the survay,the most important setneters concern also,there is not a considerable income from setnet and for young employment as a carer is very smal role.

In order to identify and estimate the population of fish and its relationship with environmental factors, sampling was done seasonally from summer 2009 to spring 2010 by electrofishing (DC, 200-300V) in Shirabad stream. Results show four identified species of fish including: Spirlin (Alburnoides eichwaldii), Sand Goby (Neogobius fluviatilis), Loaches (Paracobitis malapterura) and Chub (Squalius cephalus). The estimated population was calculated as for density in different seasons. Sand goby and Spirlin were caught in different seasons in a way that Sand Goby were estimated as the dominant species with the highest frequency (52%) in all four seasons. However, in some seasons Loaches and Chub were observed. In Shirabad stream, the presence of Sand goby was significantly and positively correlated with turbidity and water temperature and the presence of Chub had the highest positive correlation with pH levels. In addition, the presence of Spirlin were positively correlated with stream width, channel incision and water depth The presence or absence of Loaches were correlated to environmental factors such as phosphate and water discharge rate.

This study was conducted to determine the effect of replacing fish meal with soybean meal on growth rate, feed conversion ratio and chemical composition of carcass, fillet and liver in juvenile stellate sturgeon (Acipenser stellatus). As in Treatments one (F), two (S1), three (S2), four (S3) and five (S4) 0, 10, 20, 30 and 40 percent of fish meal was replaced with soybean meal, respectively. Five isonitrogenous and isocaloric diets formulated containing 44 percent crude proteins and 4374 Kcal gross energy kg-1 diet. Individual body weights of fish were measured every three week. Fish were sampled randomly from each treatment for whole body, fillet and liver proximate analysis. Based on the results, weight gain (WG) and feed conversion ratio (FCR) had significant difference among the treatments (P<0.05), as S3 and S4 diets had significantly weakest performance than any of other diets (P<0.05). FCR in fish fed on F and S1 diets were significantly higher than fish fed on other diets, while statistical significant differences were observed between S2 with two other treatments. Significant differences were found in carcass protein, lipid, and moisture content in fish fed on diets with different soybean meal levels (P< 0.05), but ash content have not significant difference among the diets (P>0.05). Significant differences were found in fillet lipid content (P<0.05), but protein, moisture and ash content did not significant difference (P>0.05). Liver proximate composition of fish did not significant difference (P>0.05).

The aim of this research is to determine the levels of polycholoro biphenil (PCBs) in skin and muscle tissues of common carp (Cyprinus carpio) and common pike (Esox lucius) fishes in the west part of Anzali wetland (Abkenar) in the two seasons, autumn 2009 and winter 2010. In each seasons, nine fishes from each species were selected randomly. The samples, transferred in cool condition and the muscles and skins of them were removed. All of the preparations organs clean up and PCBS analysis were carried with GC-ECD (Gas chromatography). Mean concentrations of PCBS were 24.36пg/g dry.w in skin 14.36пg/g dry.w in muscle tissue for E. lucius and 21.84пg/g dry.w in skin and 20.86пg/g dry.w in muscle tissue of C. carpio. In the autumn, the values was less than FDI standard and food standard Australia/AZ MRL and skin tissue of E. lucius and muscle tissue of C. carpio was over of US EPA standard values. Mean concentration of PCBS were 29.43пg/g dry.w in skin and 10.10ng/g dry.w in muscle tissue for E. lucius and 33.06пg/g dry.w in skin and 11.00пg/g dry.w in muscle tissue for C. carpio. In the winter, the value was less than FDI standard and food standard Australia /AZ MRL and skin tissue of E. lucius and skin tissue of C. carpio was over of US EPA standard values. Mean concentration of PCBs in water in the autumn (0.0042ppb) was less than recommended water quality Criteria E.P.A and in the winter (0.1938ppb) was over recommended water quality Criteria E.P.A. Mean concentration of PCBs in sediment in the autumn (4.89ng/g dry.w) and winter (4.48ng/g dry.w) was less than Interim Canadian Sediment Quality Guidelines. There were significant differences between E. lucius mussels and C. carpio skin tissue in two seasons (autumn and winter) in water and ingredient suspension. But in sediments, no significant difference was detected in autumn and winter.

Investigation of habitat conditions and identification of aquatic species in running waters is of high importance in ecological research. This study was carried out in Aras River on the eastern side of the Azerbaijan province from Jolfa to Aslandooz in 2005-2006. Fish sampling was carried out in seven stations seasonally by an electro shocking instrument. During the sampling, important water parameters including EC, IDS, DO, CO2, pH, alkalinity and hardness were also recorded. Biometrical evaluations on 1365 prey fish showed that 17 species and subspecies belonging to 6 families, Cyprinidae, Balitoridae, Cobitidae, Siluridae, Percidae, Gobiidae were present in the samples. Cyprinidae family was represented by12 species and subspecies and other fish families had only one representative. Capoeta capoeta with 56.6% had the highest frequency and was the most dispersed compared to other species in Aras River.

Kargan-rood is one of the most important rivers in the west of Guilan province. Identification of fish species of this river was carried out in 1995-96. Ten stations were selected for sampling and samples were collected monthly by using castnet, beach-seine and hook.
The 12 species belong to 5 families were identified in which family of Cyprinidae with 6 species (and 6 different genus) were the most dominant family. The identified species were:Rutilus frisii kutum, Chalcalburnus chalcoides, Capoeta capoeta gracilis, Barbus Alburnus eichwaldi, Leuciscus cephalus, Caspiomyzon wagneri, Cobitis caspia eichwaldi, Gobius kessleri, Salmo trutta caspius, Salmo trutta fario, Syngnathus abaster.