Recent Submissions

  • Expression of estrogenic response genes to different concentration of 17ß-estradiol in male mosquitofish (Gambusia yucatana)

    Rendón von Osten, J.; Aguayo-Dionet, G.; Dzul-Caamal, R.; Lara-Flores, M. (2019)
    The proximate composition, amino acids and fatty acids composition in the muscle of wild, inshore and offshore cage-cultured large yellow croaker, Pseudosciaena crocea (Richardson, 1846), were determined to identify nutritional differences. Wild fish groups showed highest content of moisture and crude protein, but the lowest lipid content. Offshore cage-cultured fish showed significantly higher content of moisture and crude protein content, but lower crude lipid content than inshore cage-cultured fish. The content of aspartic acid, glutamic acid, and alanine was higher in wild large yellow croaker than inshore cage-cultured groups, but similar to offshore cage-cultured fish. Significant lower contents of total amino acids, essential amino acids, non-essential amino acids and flavor-enhancing amino acids content were recorded in two cultured fish groups than those in wild group. While no major differences in fatty acids composition were found between wild and cage-cultured groups except for linoleic acid. The fish from offshore cages has much better nutrient profile than inshore cage cultured fish, but was still inferior compared to wild fish.
  • Shells of Bufonaria echinata as biomonitoring materials of heavy metals (Cd, Ni and Pb) pollution in the Persian Gulf: with emphasis on the annual growth sections

    Pourang, N.; Bahrami, A.; Nasrolahzadeh Saravi, H. (2019)
    Concentrations of heavy metals (Cd, Ni and Pb) were determined in soft and hard tissues (three separated shell sections) of gastropod Bufonaria echinata as well as surficial sediments collected in October 2015 from two sampling sites located in the sub-littoral zone of Qeshm Island, Persian Gulf. There were significant differences between the sampling sites for concentrations of all the three elements in the shells and sediments. But in terms of the soft tissues, in the case of Ni and Pb significant differences between the sites could be observed. In all the cases, higher levels were observed in the samples from Suza site, which may be mainly due to the proximity of this site to the relevant anthropogenic sources. Comparison of the gained data from this study with the other relevant researches shows that in most cases the levels of the elements in the soft tissues and shells either fell within the range for other world areas or were lower. The observed increasing trends of metals accumulation in the shell sections (from older to younger sections) could be mainly attributed to the gradual increase of relevant anthropogenic pollutants in the study area, especially in Suza pier, during the recent years. Generally, it can be concluded that the shells of B.echinata could be possibly employed as a biomonitoring tool for historic metals contamination in northeastern part of the Persian Gulf.
  • Effect of the probiotic, Lactobacillus plantarum on growth performance and haematological indices of rainbow trout (Oncorhynchus mykiss) immunized with bivalent streptococcosis / lactococcosis vaccine

    Soltani, M.; Kane, A.; Taheri-Mirghaed, A.; Pakzad, K.; Hosseini-Shekarabi, P. (2019)
    The present study evaluated the effect of Lactobacillus plantarum as a probiotic on the growth performance and haematological parameters of juvenile rainbow trout (Oncorhynchus mykiss) weighing 29.6±1.8 g immunized with streptococcus/lactococcus bivalent vaccine for 60 days at 16±1.5ºC. Fish were randomly allocated to 4 equal groups: probiotic (g kg^-1 feed equal to 10^8 cells g ^-1) supplemented diet group (group P), vaccinated fish fed with a normal diet (group V), vaccinated fish fed with probiotic (group P+V) and unvaccinated fish fed normal diet (group C). Results showed that weight gain, final weight, condition factor and thermal unit growth coefficient were improved in P+V group compared with other groups but was significantly different from groups V and C (p0.05) was found in RBC, Hb, MCH, MCHC and MCV levels among the different experimental groups. These data show that application of L. plantarum could be a benefit of vaccinated trout, enhancing fish growth and haematological parameters.
  • Quality enhancement in refrigerated tiger tooth croaker (Otolithes ruber) fillets using chitosan coating containing green tea extract

    Khodanazary, A.; Salati, A.P.; Bohlouli, S.; Mohammadi, M.; Sadeghi, E. (2019)
    The effects of chitosan (2%) coating combined with green tea extract (GTE) (1%) on the quality of tiger-tooth croaker (Otolithes ruber) fillets including chemical, microbiological, texture, color and sensory properties during 16 days of refrigerated storage was investigated. The color changes were significantly retared, and the texture parameteres and sensory scores were significantly improved in tiger- tooth croaker coated by chitosan, GTE and chitosan combined with GTE, compared with the control. The coincidental lowered rate of increase total volatile base (TVB) content, thiobarbitoric acid (TBA), peroxide value (POV) and free fatty acids (FFA) were obtained in tiger-tooth croaker coated chitosan+GTE. Chitosan in combination with GTE had higher inhibition on microbial growth and yielded the tigertooth croaker with higher likeness, compared with the other treatments. Therefore, fish coated with chitosan+GTE had the lowest losses in quality during refrigerated storage.
  • Effect of using various amounts of patin (Pangasianodon hypophthalmus) fish oil on physical and chemical properties of moisturizing hand cream

    Shabanikakroodi, S.; Christianus, A.; Tan, C.P.; Shabanikakroodi, S.; Ehteshami, F. (2019)
    Hand cream is used for rehydrating and improving skin properties. The skin is the first point of contact with the environment. Thus having healthy skin with proper barrier properties is quite important. The beneficial effects of fish oil on skin make it a favorable ingredient to be used in hand care products. In the present study, the efficacy and stability of various hand cream formulations using 0, 1.0, 2.5 and 5.0% of fish oil were investigated and compared. The appearance, odor, texture, and pH of formulations containing 1 and 2.5% of fish oil remained stable in very good qualities during the storage, whereas the related values to the appearance and texture of formulation containing 5.0% of fish oil at the end of 6 months of storage at 45°C were significantly (p<0.05) lower than other formulations and previous evaluations of this formulation. Weight loss was not observed in all formulations under study.
  • Blood biochemical changes in common carp (Cyprinus carpio) upon co-exposure to titanium dioxide nanoparticles and paraquat

    Banaee, M.; Tahery, S.; Nematdoost Haghi, B.; Shahafve, Sh.; Vaziriyan, M. (2019)
    Research on eliminating organic pollutants in water by using heterogeneous photocatalysts such as nano-TiO_2 abound. However, the question is whether metabolites, resulting from optical dispersion of environmental pollutants, are still toxic to aquatic organisms. Therefore, this study was designed to evaluate the effect of a co-exposure to paraquat and TiO_2-NPs on blood biochemical indices of common carp. Fish were exposed to 0.2 and 0.4 mg L^-1 paraquat with 0.125 mg L^-1 TiO_2-NPs for 21 days under different light conditions, including natural photoperiod (16 L 8h^-1 D) and complete darkness. No significant alterations in the Aspartate aminotransferase (AST), Alanine aminotransferase (ALT), Lactate dehydrogenase (LDH), Alkaline phosphatase (ALP) and Creatine phosphokinase (CPK), activities and total protein, albumin, globulin, glucose, cholesterol and triglyceride levels were observed in fish exposed to TiO_2-NPs and 0.2 mg L^-1 paraquat under normal lighting conditions. However, a significant change in blood biochemical indices in fish exposed to TiO2-NPs with 0.4 mg L^-1 paraquat (16 L 8h^-1 D) and in fish exposed to TiO_2-NPs and paraquat (under darkness). A significant decrease in the activity of Gamma-glutamyltransferase (GGT) and a significant increase in creatinine level were observed in all groups which were exposed to TiO_2-NPs and paraquat. The results of this study indicate that using 0.125 mg L^-1 nano-TiO2 in order to remove paraquat (0.2 mg L^-1) under lighting conditions can minimize the adverse effects of paraquat and its metabolites on blood biochemical indices of fish. So, using nano-TiO_2 (0.125 mg L^-1) to remove paraquat under lighting conditions can significantly reduce its toxic effects.
  • The synergistic influence of Holothuria arenicola extract and imidazole carboxamide on Cellosaurus cell line B16-F10

    Baharara, J.; Nikdel, N.; Nezhad Shahrokhabadi, Kh.; Amini, E. (2019)
    Skin cancer has been reported as a contemporary malignant cancer. Here, anti-cancer effects of sea cucumber extract (SCE) from Holothuria arenicola have been examined on melanoma cells and compared with imidazole carboxamide (Dacarbazine) as a chemotherapy medication against melanoma and Hodgkin's lymphoma. MTT assay and morphological analysis were performed to evaluate cytotoxic effects of H. arenicola extract. Also, several methods were exerted to detect cell dying by SCE and imidazole carboxamide. The MTT assay showed that B16F10 cells proliferation was blocked by SCE (IC_50=31µg ml ^-1) and imidazole carboxamide (IC_50=1600 µg ml ^-1) in a dose and time dependent manner. Apoptosis induction yield treatment occurred at IC50 concentration of SCE and imidazole carboxamide using DAPI staining, Acridine orange/Propodium iodide, PI flow cytometry and annexin/PI assay. The caspase colorimetric kit indicated that SCE and imidazole carboxamide could induce apoptosis through an intrinsic pathway. Collectively, our findings suggested that the methanolic SCE has more efficient cytotoxicity efficiency compared to imidazole carboxamide. Therefore, SCE may be considered as a futuristic marine natural product regarding prevention or treatment of melanoma malignancy.
  • Bio-functions of carvacrol-supplemented feeds on lipopolysaccharide-induced rainbow trout (Oncorhynchus mykiss Walbaum, 1792)

    Kucukgul, A.; Kucukgul, A.; Gulsafak, İ. (2019)
    To investigate the effects of carvacrol supplementation in rainbow trout induced by lipopolysaccharide (LPS), relative gene expressions levels of some pro-inflammatory cytokines and apoptosis markers in kidney and liver were measured. Fish with a mean weight of 44.71±1.33 g were studied using four different treatments with three replicates each. Inflammation and apoptosis were performed using LPS of Escherichia coli (25 µg ml ^-1) except in the control group and only carvacrol (100 µg ml ^-1 diet) containing diets were fed to this group (CAR). The last group was the infected fish fed carvacrol supplemented diet (+CAR). Kidney and liver tissues were removed 3 days after to determine the levels of interleukin-1β (IL-1β), interferon gamma (INF-γ), caspase 3 (Cas 3), caspase 8 (Cas 8) using Real-Time PCR analyses. IL-1β expressions of both kidney and liver was significantly decreased (12.9 and 2.14 fold, respectively) in LPS treated cells (p<0.05). While IFN-γ expression was up regulated in kidney, it had down regulation in liver. LPS decreased both Cas 3 and 8 expressions in kidney but increased in liver. +CAR increased expressions of IL-1β and IFN-γ compared with the control (up to 2-3 fold) in all tissues except caspase gene expressions that were similar in the control. In all tissues, IL-1β and IFN-γ expressions increased in +CAR group, expect IFN-γ in the kidney. However, Cas 3 and 8 expressions including apoptosis was induced by up-down regulations in all tissues compared to LPS-injected fish. The results showed that carvacrol had pro-inflammatory and apoptotic effects especially on liver tissue of LPS-induced inflammation model of Oncorhynchus mykiss.
  • Determination of some heavy metal levels in three freshwater fish in Keban Dam Lake (Turkey) for public consumption

    Caglar, M.; Canpolat, O.; Selamoglu, Z. (2019)
    Due to industrialization, a number of factories and human population have increased rapidly. As a result, the amount of waste matter such as heavy metals released to the environment has been increased. Specifically aquatic systems are more sensitive to heavy metal pollution and the gradual increase in the levels of such metals in aquatic environments, mainly due to anthropogenic sources, have become a problem of primary concern (Ashraf et al., 2012). The natural aquatic ecosystems may extensively be contaminated with heavy metals released from domestic, industrial and other anthropogenic activities (Kamaruzzaman et al., 2011).
  • Zooplankton of Çat Dam Lake (Malatya-Turkey) with a new record for Turkish rotifers Lecane intrasinuata (Olofsson, 1917)

    Saler, S.; Bulut, H.; Karakaya, G. (2018)
    There are many studies on the zooplankton of Turkish lakes, many of which are about seasonal fluctuations, distribution and hydrological changes. In recent years many scientists focused their attention on the zooplankton of Turkish inland waters (Dumont and De Ridder, 1987; Segers et al., 1992). The family Lecanidae consists of one genus, Lecane Nitzsch, 1827 with about 200 species. This genus is the most common rotifer species inhabiting in various aquatic environments (Segers 1994, 1995, 2008). They are from Monogonont rotifers and are diagnosed by the retractile head, the structure of the foot and toes and by the trophy in the female (Segers, 1995). Lecanids have got a loricate body and the body is compressed dorso-ventrally. The dorso ventral plates are connected by a flexible membrane. The feet have got two primitive segments of which only the posterior is movable. Toes varied remarkably within individuals of the same species (Arora, 1965). Their bodies resemble each other which cause difficulties in identifying species (Segers et al., 1992).)
  • Fish assemblage and structure as well as hydrological parameters at Karatoya Fish Sanctuary, Panchagarh, Bangladesh

    Md. Rashidul, I.; Md. Jewel, M.; Shirin, S. (2019)
    Spatiotemporal variations in fish assemblage structure was studied from January to December 2015 in order to understand the impacts of the sanctuary on ichthyo-faunal diversity and to determine the indices and major hydrological factors in six sampling stations of Karatoya Fish Sanctuary sectioned in the River Karatoya. A total of 69 fish species were obtained from this sanctuary including 21 threatened species where Aspidoparia jaya, Pethia ticto, Puntius sophore, Canthophrys gongota and Barilius barna were the major contributory species (>4.17%) both in space and time. The uppermost species richness and abundance were viewed in January and lowest in May. Based on analysis of similarities (ANOSIM), fish assemblages were significantly different in all stations (p<0.001, R=0.15) and months (p<0.001, R=0.62). Through two-dimensional nonmetric multidimensional scaling (nMDS) and cluster analysis based on Bray-Curtis similarity index, assemblages were alienated into two groups at a value of 42% and 28% partition for station and month, respectively. Canonical Correspondence Analysis (CCA) recognized considerable relations between the number of fishes and hydrological parameters where dissolved oxygen (mg L ^-1) and water temperature (ºC) were the main leading factors in shaping the fish assemblage structure.
  • Scale characteristics of the bloom event: A case study in the Iranian coastal waters of the Southern Caspian Sea

    Makhlough, A.; Nasrollahzadeh Saravi, H.; Eslami, F.; Keyhansani, A.R. (2019)
    Nutrient enrichment in water and sediments due to excessive anthropogenic activities in recent years has caused excessive algal growth in the Caspian Sea. The current study was conducted to determine the abundance of phytoplankton community, the dominant species and chlorophyll-a [Chl-a] concentration during algal blooms in the Iranian coastal waters of Caspian Sea through four seasons from 2013 to 2014. The minimum and maximum phytoplankton abundance recorded were 73±31 and 505±55 million cells m-3 in summer and winter, respectively. The median concentration of Chl-a increased to 5.81 mg m -3 in autumn, as compared to the annual median value (2.43 mg m^-3 ). The results indicated that the bloom started in autumn and it continued falling with a low concentration during winter (Chl-a: 2.59 mg m^-3). The three species Stephanodiscus socialis, Binuclearia lauterbornii and Thalassionema nitzschioides were classified in medium bloom class (100-1000 million cells m^-3) in spring, summer and autumn, respectively. While in winter Pseudonitzschia seriata (harmful species) and Dactyliosolen fragilissima were classified in medium bloom class with high relative frequency. The scaling of bloom abundance revealed that bloom initiation coincided with 10 million cells m^-3 of the dominant phytoplankton species. The bloom at the regions with more than 100 million cells m^-3 of total phytoplankton abundance and dominant species was overlapped with the bloom regions based on Chl-a concentration.
  • Effect of different levels of iron sulfate on some haematological parameters of ship sturgeon, Acipenser nudiventris

    Hosseini, S.H.; Kamali, A.; Yazadani, M.A.; Khara, H. (2019)
    The present study was conducted to examine different dietary levels of iron (FeSO4) on some haematological parameters of ship sturgeon, Acipenser nudiventris including red blood cells (RBC), white blood cells (WBCs), differential WBCs, hematocrit (Hct), Hemoglobin (Hb), the mean corpuscular hemoglobin (MCH) and the mean corpuscular hemoglobin concentration (MCHC), the mean corpuscular volume (MCV), immunoglobulin (IgM), ferritin, transferrin and plasma Fe^2+. Four experimental treatments and one control group with three replicates were considered for the experiment. The experimental treatments were fish fed experimental diets containing different levels of FeSO_4 i.e. 100, 200, 250, and 300 mg kg. diet^-1. After 60 days, there were significant differences between experimental groups in terms of WBCs, lymphocytes, neutrophils, monocytes, eosinophils, MCH and MCHC, MCV, total plasma protein, IgM, ferritin, transferrin and plasma Fe^2+ (p<0.05). In the treatment fed 100 mg. iron kg. diet^-1, more levels of IgM and total plasma protein were observed compared to other experimental groups (p<0.05). The highest values of neutrophils, monocytes and MCHC were found in control fish whereas MCV, MCH and eosinophils values were higher in the treatment fed 200 mg. iron kg. diet^-1 (p<0.05). Also, more WBCs were observed in 250 mg. iron kg. diet^-1 treatment than in other groups (p<0.05). The values of lymphocytes, RBC, Hct, Hb, ferritin, transferrin and plasma Fe^2+ were higher in fish fed 300 mg. iron kg. diet^-1 compared to other experimental groups (p<0.05). In conclusion, our results showed that the supplementation of ship sturgeon diets with high levels of iron enhances the RBC, Hct, Hb, ferritin, transferrin and plasma iron.
  • The effects of Rosmarinus officinalis essential oil on the quality changes and fatty acids of Ctenopharyngodon idella

    Roomiani, L.; Ghaeni, M.; Moarref, M.; Fallahi, R.; Lakzaie, F. (2019)
    The effects of the use of essential oil of Rosmarinus officinalis on the chemical quality and fatty acids of fish fillets of Ctenopharyngodon idella were investigated during frozen storage at -18 ºC for 6 months. Fish fillets were divided into three groups; the control (C) without rosemary essential oil, the second group with 0.2 % rosemary essential oil (A) and the third with 0.4 % (v/v) rosemary essential oil (B). According to compositional analysis of the rosemary essential oil by GC-MS, the α-pinene (31.91%) and 1, 8- cineol (14.66%) were the predominant components. Results showed that there were no significant differences of protein in group C and A, but differences were seen between A and B (p<0.05). A significant decrease in lipid was obtained throughout between groups during storage (p<0.05). There were no significant differences of pH between three groups at storage periods (p>0.05). Effect of rosemary essential oil showed that the least changed fatty acids were on polyunsaturated fatty acids (PUFA), monounsaturated fatty acids (MUFA) and saturated fatty acids (SFA), respectively. Microbial results showed TVC content of fillets fish did not exceed the limit during storage period for A and B Groups (< 7 log CFU g^-1 ). Rosemary essential oil at 0.2% and 0.4 % was effective in controlling the chemical compositions and fatty acids, but sensory attributes reveal a decreasing trend in the attributes like color, odour, taste, firmness and general acceptance for two groups (p<0.05), but group A indicated better scores than Group B at the end of the storage period.
  • Effects of different cooking methods on minerals, vitamins and nutritional quality indices of grass carp (Ctenopharyngodon idella)

    Golgolipour, S.; Khodanazary, A.; Ghanemi, K. (2019)
    This study aimed to evaluate the nutritional value (proximate composition, fatty acid profiles, vitamins and minerals) contents and also nutritional quality indices (NQI)) of grass carp (Ctenopharyngodon idella) prepared according to common consumer techniques: raw, poached, steamed, microwaved, pan-fried and deep-fried (in olive oil). In comparison to raw fish fillets, when grass carp was cooked there was an increase in protein, lipid and ash contents. Cooking methods had no significant effect on total n-3 fatty acids except for frying fillets. Lowest and highest content of n-3 was shown in deep-fried and pan-fried samples, respectively. Total n-6 fatty acid of cooked samples increased in comparison to raw samples. Na, K, Mg, P and Zn contents of boiled fish fillets significantly decreased. None of cooking methods had a significant effect a vitamin D. However, vitamin A, B_1 and B_3 contents of cooked fish significantly decreased.
  • Investigation of physicochemical factors, chl-a and primary production in Mahshahr Creeks (Northwest Persian Gulf)

    Ghotbeddin, N.; Mosavi Dehmordi, L. (2019)
    The study on physicochemical factors and primary production of the aquatic ecosystems is important to know the characteristics of the environment and capacity of recharge. Mahshahr Creeks are the most important creeks in the Northwest Persian Gulf, Iran. In this study, variations in physicochemical factors, chl-a, and primary production in creeks of Mahshahr, Zangi, and Moussa were evaluated for 2 months of every season of 2014. The following variables were analyzed: nitrate, phosphate, nitrite, silicate, temperature, salinity, DO, pH, conductivity, turbidity, light, chl-a, primary production and phytoplankton abundance. The maximum amount of chl-a (1.6 mg m^3) was observed in Moussa Creek in April while the minimum amount (0.1 mg m ^-3) was seen in Moussa in July. The highest (1.19 gc m^-2 day^-1) and lowest (0.1gc m^-2 day^-1) amount of primary production were observed at the entrance of Moussa Creek in April and in Zangi Creek in November, respectively. The maximum and minimum abundance of phytoplankton was observed in April and October, respectively in all study areas. The results of correlation test between the studied factors revealed that primary production has a significant relationship with nitrite, chl-a, phytoplankton abundance and light. Primary production in these creeks is relatively high in April and is attributed to the uptake of nutrients including nitrate and phosphate from shallow waters entering these creeks, sufficient light and suitable temperature, but in other months the production is low.
  • Evaluation of incubation temperatures on DNA damages of the Caspian trout (Salmo trutta caspius Kessler, 1877) single cells through developmental stages by Comet assay

    Alizadeh Sabet, H.R.; Kalbassi, M.R.; Pourkazemi, M.; Sadeghizadeh, M. (2019)
    Caspian trout (Salmo trutta caspius Kessler, 1877) as endemic migratory fish, possessing great ecological economic and biodiversity value. Among the habitat drivers, temperature related effects on the genome were considered in this research. During the embryonic developmental stages, genomic alterations of single cells were assessed by Comet assay. After artificial propagation of wild broodstocks, the batches of eggs, were transferred to incubators with constant temperatures, REDD water recycling, 3 stages water filtration, UV-C application on effluent of each incubator and DO–pH–temperature control. Samples were collected from normal (8°C), cold (4°C) and warm (12°C) treatments on eyed egg, alevin and larval stages. Single Cell Gel Electrophoresis were applied on samples for evaluation of Comet Tail length (TL), DNA in tail (DT) and Tail Moment (TM) indices as DNA damage markers. Comparison between mean values of Comet TL index indicated 85.19 ±9.2, 9.88 ±2.3 and 256.54±14.6 for 4, 8 and 12°C treatments, respectively. DT were 18.07±6.3, 9.72±1.9 and 31.47±2.8 and then TM were measured as 15.27± 4.1, 1.21±0.2 and 95.25±8.6 for 4, 8, and 12°C treatments, respectively. Significant difference between thermal treatments (p<0.05) observed. Warm treatments demonstrated greater DNA damage in compare with others. TM explained better information in comparison with TL and DT in all analyzed samples. In conclusion, temperatures out of the range of the optimal conditions could significantly affect Caspian trout genome which could be the subject of management considerations pertaining to Caspian trout stocks rehabilitation and captive rearing strategies.
  • Oral administration of garlic powder (Allium sativum) on growth performance and survival rate of Carassius auratus fingerlings

    Dadgar, Sh.; Seidgar, M.; Nekuiefard, A.; Valipour, A.R.; Sharifian, M.; Hafezieh, M. (2019)
    This study was carried out to evaluate the effect of different levels of garlic (Allium sativum) on growth survival and nutritional characteristics of goldfish (Carassius auratus). For this purpose, 180 goldfish with an average initial weight of 1.18± 0.08 g were introduced randomly into 12 aquaria (50×30×40 cm) in 4 groups, with 15 fish in each group. Treatments were fed on a basal diet for one week, followed by experimental diets for eight weeks. Garlic powder was added at levels of 0 (Control), 0.5, 1 and 1.5 mg kg^-1 to commercial diet. At the end of the experiment, growth and survival rates and feed performance were evaluated. There was no significant difference in growth rate and feed efficiency between treatments, although they were better in the 0.5% level. The highest survival rate was achieved in the 0.5% treatment that showed a significant difference compared to the control diet (p<0.05). The best growth performance and feed efficiency were obtained in fish fed the 0.5% garlic powder diet.
  • Stock identification of Arabian yellow fin sea bream (Acanthopagrus arabicus) using shape of otolith in the Northern Persian Gulf and Oman Sea

    Doustdar, M.; Kaymaram, F.; Seifali, M.; Jamili, Sh.; Bani, A. (2019)
    Otolith shape analysis is one way to identify stocks of different fish species in the marine environment. Length, width, area, perimeter, form factor, aspect ratio, roundness, circularity, ellipticity and rectangularity analyses of otoliths were undertaken to assess patterns of spatial and temporal stock structure of a wide-ranging fish, the Arabian yellow fin sea bream Acanthopagrus arabicus. Fish were sampled from 125 stations across the distribution range of the species in the Northern Persian Gulf and Oman Sea from June 2014 to May 2016. Analysis of morphometric parameters of otolith showed the minimum size in Khuzestan waters and the West Strait of Hormuz and the maximum size in the East Strait of Hormuz. In Bushehr waters, form factor showed the lowest and circular factor showed the highest frequency. These findings are in agreement with the irregularity in otolith margin of this area. The highest aspect ratio of otolith indicated higher growth in Khuzestan Waters. The thinner and longer otoliths were identified in the East Strait of Hormuz region. Further, rectangularity ratio factor in the Bushehr and West Strait of Hormuz waters was higher in comparison with other regions and this finding confirmed the quadrilateral otolith shape of this region. There are significant differences among otolith morphometric variables of the A. arabicus (p<0.05). The result of discriminant analysis on morphometric parameters indicated that 53/8 percent were in their geographic location accurately.
  • Viral nervous necrosis (VNN) an emerging disease caused by Nodaviridae in aquatic hosts: Diagnosis, control and prevention: A review

    Zorriehzahra, M.J.; Adel, M.; Dadar, M.; Ullah, S.; Ghasemi, M. (2019)
    Betanodavirus is one of the two genera making up the family Nodaviridae and is the etiological agent of viral nervous necrosis (VNN, also known as viral encephalopathy and retinopathy or VER). The virus infects a large range of host species in more than 50 species of marine and freshwater fish worldwide from different geographical areas and the known host range continues to expand as new species of fish are used for aquaculture. The disease is characterized by vacuolating necrosis of neural cells of the brain, retina and spinal cord and causes up to 100% mortality in larval and juvenile fish, and can cause significant losses in older fish. The lack of knowledge about control and prevention of the disease makes the problem serious and impedes development of management approaches. Therefore this review focuses on current knowledge and future perspectives of viral nervous necrosis in the aquaculture industry with special focus on the type of diagnosis, control and prevention of the disease.

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