16 research outputs found

    Genetic variability and differentiation of rainbow trout strains in Iran

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    To determine the genetic structure and differences of rainbow trout, variations in 9 microsatellite loci in four stocks of rainbow trout from Mazandran, Iran were examined. Three samples were introduced from Norwegian, French stocks, and one was from Iranian stocks rearing in North of Iran. Most but not all loci were polymorphic in all stocks. There was substantial genetic differentiation among populations, with an average FST value of 0.065. The four stocks averaged 5.2–7.4 alleles per locus, with average heterozygosities of around 0.625 to 0.762. A large variation in observed hetrozygocity, averaged over all samples was observed among loci and ranged from 0.015 in OTSG474 to 0.850 in OTSG249. Nine of 20 tests for Hardy – Weinberg expectations gave significant deviations. The cause(s) of these deviations are unknown. The Norway strain was significant deviations from HWE in all 5 polymorphic loci. The degree of differentiation among strain or Nei Genetic Distance compared pairwise accorded well with their likely genetic connectivity. Two of the strains, Iranian and Norway had the highest Nei Genetic Distance (0.213) and were different in all loci except for OTSG3. The level of genetic variation in the domesticated rainbow trout strains that are farmed in European countries (French, Norway) and Iran did not differ significantly neither within nor between the countries, but the highest pronounced difference was comparable with that of the Norway and Iran strains

    Investigation of the Fire Effects on Some Physico-Chemical Characteristics of Soil (Case Study: Miankaleh Rangeland, Iran)

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    Fire is one of the ecological factors that can have positive and negative effects on ecosystem processes. Nevertheless, prescribed burning is considered to be an important tool for grassland management, particularly to manipulate the balance between grasses and shrubs (Scheintaub et al. 2009). In Iran, for example, Khodagholi et al. (2001) in the Samirom rangelands of Isfahan Province suggest that fire reduces the shrubs cover and production and leads to the expansion of grasses. Sharifi and Imani (2006) showed that in the semi-steppe of Khalkhal Province shrub cover decreased in contrast to permanent grasses after fire was applied. However, others report that fire can reduce production and plant diversity due to affects on the range soil properties. This research investigated the effects of fire on some soil physico-chemical characteristics in the Miankaleh rangeland in northern Iran

    Mineral Content in Some Species of Leguminosae in Bandar Torkaman Plain Rangelands, Iran

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    Improving the forage quality and balance of their minerals in rangeland ecosystems is important for rangeland managers to improve livestock productivity (Mohamed et al. 2003; Epstein and Bloom 2005). This research investigated the amount of several minerals; Calcium (Ca), Phosphorus (P), Potassium (K) and Magnesium (Mg), in some important species of Leguminosae including Medicago sativa, Trifolium repens, Trifolium pratense and Lathyrus pratensis, that are grazed by livestock in the Bandar Torkaman plain rangelands in north of Iran

    The investigation and morphological study of two type of Crass carp: Ctenopharyngodon idella and survival rate of their larvae

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    The two groups of grass carp, have been propagated in North and South fish farms and then the larvae were transferring to Abziroshd and culture fish farm of Mazandaran. The fingerling at eight weight classes of 2 to 500 gram were investigated morphologically and some morphometric and meristic were compared. The South grass carp was significant difference (P<0.05) with the North, in case of weight with the same length, number of vertebral and gill raker. The coefficient of variance (CV) of meristic characters of South Grass carp was in the range of 1.2 to 9.8 while in Mazandaran grass carp 2.8 to 8.6. This CV illustrate the low variance in both population. This research study showed that the two stocks can be regard as difference races from one ancestor

    Heritability and selection response estimation of growth rate in common carp (Cyprinus carpio) of Caspian Sea

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    The Common carp is the most important culture fish in the word, that can be consider as domestic fish. The Common carp of Caspian Sea is one of the economic fish, that have some morphenological differences, resistance in salt water and better quality in meet with domestic once and for using this fish in culture system, it is necessary to establish genetically parameters especially the heritability for selection purpose. The present study have been started from 2007 and lasted 3 years. The breeders were collected from the Gomishan station in south-east of Caspian Sea by fisherman and stocked in S.Rajaei fish restocking center and propagate based on the routine propagation technique in this farm. For heritability estimation a factorial crosses by 7×7 fish were done. Therefore, the fingerlings of 49 crosses were achieved, that kept first separately fiberglass tank and then in pond separately. Weight and length of fish were choice for heritability estimation. The average weight of juvenile common carp in 3 sampling stage of 90, 180 and 360 days, were 5.9, 35.7 and 84.7 gram and length of 9.6, 14.7 and 19.2 cm respectively. The heritability estimation for weight was 0.26 and length 0.25. Selection response based on selection difference by collection the more average breeders among their progeny were 36.4 g that means by selection every generation, there is about 4 percent improving in fish weight

    Investigation of situation of propagation and culture of rainbow trout in north of Alborz

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    The aquaculture activity in provinces of north of Iran, in spite of fast progressive and possess a series of achievement and success, there was some failure, difficulties, limitation and restriction. To planning for further expansion in this failed, this study is managed. The culture of rainbow trout is practice in individual farms, small farms, water resources, earthen ponds, recycling ponds etc, which each method have its potential, failure and limitation that are consider in the present work. At the end, based on the situation of production in past years, and considering each of factors mentioned above, the success, failure, difficulties, limitation and restriction points of aquaculture of rainbow trout in technical poin of view are investigated and some command for improvement for each production method are presented. The development of aquaculture in recent years is based on extension of farms and increasing density of fish in fish pond. In contrast of many production activities, the propagation and culture of fish is inconstant work. This variability makes a potential for better income, occupation and job, increasing in production etc. This study make a better planning using this activity

    The feasibility of creating a natural habitat for spawning, bony fish in the Caspian Sea in order to preserve biodiversity and genetic risk

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    The purpose of this study was to investigate the possibility of natural reproduction of indanger fish in the southern Caspian Sea in Tajan, Haraz,Sardabrood and Chalos rivers, and identify suitable habitats for this species in the study area as a genetic reserve.Sampling of physical and chemical parameters of water, macrobenthic invertebrates and fish fauna was conducted seasonaly in each rivers at selected stations from febrary 2010 during one year. Macrobenthic invertebrate sampling were used bySorber sampler and fish was collected by gill net and electroshocker set with a voltage of 1.7 A and 100-300 V. A total of 53 taxa of macrobenticinvertabrateshave been identified in the four mentioned rivers, in which Tajanriverconsisted of 47 taxa with highest richness.20 species of fish were determined in the studied rivers that 6 of them were non-native species.The results showed that the predominant identified fish species were native in the river. The fish species diversity increases as one moves from the headstream towards the estuaries of the two studied Sardabrud and Chalus rivers.The results of this study showed that the relative abundance of fish species resistant to pollution and hard environmental conditions were much more that sensitive species. physicochemical parameters of water such as; water temperature, DO, BOD5, pH, TSS, TDS, EC, turbidity, nutrients, biodiversity index such as Shanon index, EPT, HFBI, EPT/CHIR, nutrition functioning group and present or absent of fish species showed that there are significant decrease in water qualities from upstraem ratio to down stream (For example, in Tajan river water turbidity varied from 0 at station 1 to 333 NTU at station 6, Which is strongly influenced by sand workshops. As well as the activities of a significant impact of fish farming workshop on the Haraz river water quality). The minimum of HFBI index was 2.84 at station 1 and the maximum was recorded at station 5 with 6.01, and there is not any possibility to natural reproduction of migrated species that are dominant and indanger at downstream. Conditions for natural reproduction of this species in the rivers of srdabrood and Chalus there is to some. In Shahid- Rajaei dam the maximum relative abundance of fish species belonged to Capoeta capoeta, Luciobarbus capito and Squalius cephalus, respectively. These species have different age, length and weight stuctures at Shahid- Rajaei dam inhabitant, and the resourval of this dam and it,s upstream have been preparing auch a favorabile condition that seems there are potentioal of introductionand inhabitant of some of the Migratory and indanger fish species such as Barbels, Sturgeon, Alburnus chalcoides and etc. as genetic reserve for biodiversity preservation

    Increasing growth rate of Salmo trutta caspius by selection (Phase 1)

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    The management of genetically brood stocks of Salmo trutta of Caspian Sea in order to restocking for longe time harvesting and culture of fish in intensive system, has been little investigated, in contrast with European stocks. Salmo trutta Caspius is very important in biological and genetically point of view. This fish as gene bank valid for breeding improvement, hybridization and new cold species for culture, can be used. This study begain in 2007 and lasted 3 years in Bahonar, kelardasht of Iran. The breeders were 27 pairs. Each female have been crossed by 3 male. Eggs and larvae as well as the fingerlings reared separately of each crosses. The best fingerlings of 5, 20 and 100 gram were collected after 3 period of challenge. At the final 300 brood stocks in two groups were remained and stocked for artificial propagation. For heritability estimation in 4 stages sampling the weight and length were measured and it was 0.47 and 0.50 respectively. In case of molecular study the quality of DNA extract from the fin of breeders and their progeny by phenol-chloroform was good for PCR test. The heterosigosity test for Ho and He for each station and sites except for SRUTTA12 and STRUTTA59, the He was greater than Ho. Shaton Index and Hardy-Weinberg equilibrium for station and sites for male and progenies, the OM24showed deviation from H-W equilibrium. In case of similarity and genetic distance based on Nei (1972), the highest distance were in case of male and female, and were the least between fingerlings and male brood stocks

    Study on physico-chemical characteristics of water in the southern of Caspian Sea

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    In this study, the characteristics of physico-chemical parameters of water done in coastal part of the southern Caspian Sea during 2010-2011 (four seasons) in 8 transects (Astara, Anzali, Sefidrour, Tonkabon, Noshahr, Babolsar, Amirabad and Torkman). For measurement of water quality parameters, 480 samples were collected in different water layers by using of APHA standards methods. According to modeling and statistical methods was used multivariate for evaluation of factor analysis (MFA) in general groups and discriminant analysis (MDA) for spatial and temporal with water quality parameters. The statistical procedure of MFA was used for data reduction and finally six factors selected with about 80.48 percent of total variances related to them. The statistical procedures of MDA were used for the role of spatial and temporal of water quality parameters in different water layer. The function one gave eight parameters (pH, salinity, EC, DO, NO^3-, water temperature, NH^4+ and N^-total) affording more than 80, 67, 80, 77 and 71 % correct assignations (return to the same transects) in spatial analysis. In all transects during four seasons, function one gave five parameters (water temperature, salinity, EC, NO^2- and NH^4+) to afford 100, 100, 100, 97 and 97 % correct assignations in temporal analysis. The results showed that, the average amounts in light penetration layers during four seasons were for EC(15.04±0.18ms/cm), pH(8.38±0.01unit), salinity (10.31±0.16g/l), DO(5.67±0.09ml/l) and water temperature (18.28 ±0.72°C). The average amount of nutrients for parameters such as organic and inorganic phosphorus, total phosphorus, NO^2-, NO^3-, NH^4+, N^-Total and SiO_2 were 0.50±0.02, 0.32±0.01, 0.82±0.02, 1.76±0.10, 0.10±0.01, 1.51±0.10, 46.82±1.80 and 8.60±0.29µM, respectively. The average amounts in dark layers during four seasons were for EC (15.46±0.38ms/cm), pH (8.34±0.03unit), salinity (10.70±0.35g/l), DO (4.55±0.13ml/l) and water temperature (9.62 ±0.16°C). The average amount of nutrients for parameters such as organic and inorganic phosphorus, total phosphorus, NO^2-, NO^3-, NH^4+, N^-Total and SiO_2 were 0.54 ±0.05, 0.33 ±0.02, 0.87±0.06, 1.92±0.21 , 0.08± 0.01, 1.55±0.25, 45.10±3.25 and 10.05±0.62 µM, respectively. The average amounts of light penetration in all transects during four seasons 4.49±0.38 meters. The maximum light penetrations during spring, summer, fall and winter seasons were 9, 8, 8.20 and 7 meters, respectively. The maximum water temperatures in light and dark layers were 32.36 and 11.50°C. Also, the maximum differences about thermocline temperature during summer and fall seasons were 19.6°C and 10°C, respectively in southern part of Caspian Sea. Data in spatial analysis were not significant (p>0.05), it means if add or removed any transect did not change occurred. But in temporal analysis were significant (p<0.01), and it means no way remove any seasons for a research work on Caspian Sea in southern part. In those transects with 100m depth. Water temperature is only highly effective parameter between other parameters. In function 1 between 3 functions in transects with 100m depth water temperature with 60% variance was the main role and effective between different seasons in depth part were very high

    The global burden of cancer attributable to risk factors, 2010-19 : a systematic analysis for the Global Burden of Disease Study 2019

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    Background Understanding the magnitude of cancer burden attributable to potentially modifiable risk factors is crucial for development of effective prevention and mitigation strategies. We analysed results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 to inform cancer control planning efforts globally. Methods The GBD 2019 comparative risk assessment framework was used to estimate cancer burden attributable to behavioural, environmental and occupational, and metabolic risk factors. A total of 82 risk-outcome pairs were included on the basis of the World Cancer Research Fund criteria. Estimated cancer deaths and disability-adjusted life-years (DALYs) in 2019 and change in these measures between 2010 and 2019 are presented. Findings Globally, in 2019, the risk factors included in this analysis accounted for 4.45 million (95% uncertainty interval 4.01-4.94) deaths and 105 million (95.0-116) DALYs for both sexes combined, representing 44.4% (41.3-48.4) of all cancer deaths and 42.0% (39.1-45.6) of all DALYs. There were 2.88 million (2.60-3.18) risk-attributable cancer deaths in males (50.6% [47.8-54.1] of all male cancer deaths) and 1.58 million (1.36-1.84) risk-attributable cancer deaths in females (36.3% [32.5-41.3] of all female cancer deaths). The leading risk factors at the most detailed level globally for risk-attributable cancer deaths and DALYs in 2019 for both sexes combined were smoking, followed by alcohol use and high BMI. Risk-attributable cancer burden varied by world region and Socio-demographic Index (SDI), with smoking, unsafe sex, and alcohol use being the three leading risk factors for risk-attributable cancer DALYs in low SDI locations in 2019, whereas DALYs in high SDI locations mirrored the top three global risk factor rankings. From 2010 to 2019, global risk-attributable cancer deaths increased by 20.4% (12.6-28.4) and DALYs by 16.8% (8.8-25.0), with the greatest percentage increase in metabolic risks (34.7% [27.9-42.8] and 33.3% [25.8-42.0]). Interpretation The leading risk factors contributing to global cancer burden in 2019 were behavioural, whereas metabolic risk factors saw the largest increases between 2010 and 2019. Reducing exposure to these modifiable risk factors would decrease cancer mortality and DALY rates worldwide, and policies should be tailored appropriately to local cancer risk factor burden. Copyright (C) 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.Peer reviewe
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