Determination of oil pollutant (water, sediment and fish) in the southern part of Caspian Sea

This study was conducted to determine 16 Polyaromatic Hydrocarbons (16 PAHs) concentrations in water (during four seasons) and surface sediments (during summer and winter) at eight transects (Astara, Anzali, Sefidroud, Tonekabon, Nowshahr, Babolsar, Amirabad and Turkman) in the southern of Caspian Sea in 20102011. 94 samples of water and 45 samples of surface sediments were collected at 10, 50 and 100 meters depths. In addition, 28 samples of fish (Cyprinus Carpio) were collected during winter and spring. All samples were prepared by Soxhlet and extracting processes and then determined using High Performance Liquid Chromatography (HPLC) instrument. Results of current study showed that mean concentration and standard error (±SE) of 16PAHs water were observed 232 (±77), 1268 (±808), 538 (±190) and 151 (±53) µg/l in spring, summer, fall and winter, respectively. In addition, annual mean contents and standard error (±SE) of 16PAHs water were registered 24.10 (±8.12) µg/l. The Hazard Quotation (HQs) were calculated more than unit and belong to Benzo(a)pyrene and Dibenzo(a,h)anthracene compounds. Mean concentration and standard error (±SE) of 16PAHs sediment were observed 0.77 (±0.23) and 1.21 (±0.64) µg/g.dw in summer and winter, respectively. Also, the annual mean contents and standard error (±SE) of surface sediments were observed 0.93 (±0.33) µg/g.dw. The Hazard Quotation (HQs) were calculated more than unit and belong to Fluoranthene, Benzo(a)anthracene, Chryseneand Benzo(a)pyrene. The annual mean contents and standard error (±SE) of edible tissue of Cyprinus Carpio mussels were observed 2.21 (±0.42) µg/g.dw. Annually, pattern of 16PAH compounds were obtained 10, 70, 12 and 8% for 3,4,5, and 6 rings, respectively. Four ring compounds had high content and percentage and 2 ring was not observed in all samples of water. Also, pattern of 16PAH in surface sediments were obtained 31, 56 and 14% for 3, 4, and 5 rings, respectively. Four ring compounds had high content and percentage and 2 and 6 rings were not observed in all samples of surface sediments during two seasons. Result of Diagnostic Ratios analysis (DRs) of sediments showed that the source of oil compounds were petrogenic and pyrogenic in summer and winter, respectively. Based on DRs in water and sediments were observed oil compounds were either petrogenic or pyrogenic with different percentage in the southern Caspian Sea. In conclusion, the results revealed that in the some transects the 16PAHs concentrations of water were above the threshold levels and more petrogenic (85%) sources which represented polluted condition in this area. 16PAHs concentrations of sediments were below the threshold levels and conditions for this region were showed unpolluted. Also, the Caspian Sea sediments were classified in Class 2 (Fair). According to results of the evaluation’s risks to human health associated with consumption of the mussels containing 16PAHs suggest that there is risk for humans

A survey on some risk factors and evaluation of their impacts on streptococcosis in rainbow trout farms in east of Mazandaran province (Haraz River)

One of the most important bacterial fish diseases which has caused some outbreaks in rainbow trout farms in Iran is streptococcusis .The farmers were suffering from huge economic losses due to the disease outbreaks in different rainbow trout farms in Iran. The aim of our study was to determine rate of streptococcusis incidence in different stage of growth in farmed rainbow trout in Haraze River, Mazandaran province. Fish and water samples were randomly collected and measured of randomly in10 selected farms, monthly throughout a year. After clinical observations, Isolation and recognition of strep strains were made using biochemical tests. Some Environmental factors include Nitrate, Nitrite, Temperature, pH, Ammonia and DO measured during sampling periods. According to our results 4.6% of juvenile samples showed clinical singe of streptococcusis while only0.7% of them had strep. Contamination .These rates in adult samples were 8.9 and 1 percent respectively. Major isolated bacterial strain was Streptococcus uberis. Incidence of streptococcusis in rainbow trout 20% affected by fluctuation of Nitrite, temperature and DO. Management of these factors can decrease rate of disease outbreaks

Creation of cryopreservation bank of bony fish

In this study, 11 male of Caspian trout (Salmo truta caspius) (with mean length and weight 37/8 ± 5/3 cm and 523/3 ± 24/7 respectively) and 23 male of Caspian kutum (Rutilus frisii kutum) (with mean length and weight 36/1 ± 7/1 cm and 631/3 ± 21/6 g respectively) were evaluated. All the fish were good at the initial examination of sexual maturity. After sperm sampling, their quality were tested. In this step, the parameters such as motility, duration of mobility, density, pH and osmolality were measured. After this stage, the sperm samples of Caspian trout in the ratio 1: 3 were diluted with the aqueous solution containing compounds (0.3M Glucose, 10% Methanol, 10% egg yolk) and the freezing process was done manually and the sperm was frozen in liquid nitrogen. The sperm samples of Caspian kutums were diluted (ratio of 1: 3) with two soluble diluent containing compounds (350 mM glucose, 30 mM Tris and 4% Polyethylene glycol) and (350 mM glucose, 30 mM Tris and 2% Glycerol) and were frizzed automatically by Planner Kryo instrument and placed in liquid nitrogen. The sperm samples were thawed 1 to 3 months after the date of first freezing and their quality were assessed by measuring percent and timing motility. The results showed that the obtained semen volume of Caspian trout was more than Caspian kutum. Moreover, percentage of motile sperm, timing motility and sperm density of Caspian trout were higher than those of Caspian kutum but osmolality and pH of Caspian trout were lower than those of Caspian kutum. Over time, the percentage of sperm motility and mobility for both species declined compared with fresh samples. After thawing, percentage of motile sperm and timing motility of Caspian kutum were lower than those factors Caspian trout. The results showed that the sample of Caspian kutum sperm that were diluted by ethylene glycol after thawing and were immotile ll of them. However, the samples were diluted by glycerol, after thawing, were alive and motile. According to the results, it seems very important species differences that must be fully considered in the process of freezing sperm. The use of a single protocol would not be successful in cryopreservation because the reaction of sperm against to chemical agents is variable. Therefore, it is essential to get the right information to protect valuable Caspian fish by using cryopreservation. Further studies on the characteristics of each species, as well as the freezing process take appropriate diluent

Study on viral nervouse necrosis (isolation, characterisation and pathogenesis) in golden grey mullet in the Caspian Sea and study of pathogenecity and possibility of transmission to the other fish species (Sturgeon fishes, Rutilus frisii kutum and reared Rainbow trout and Carp)

Study on Viral Nervouse necrosis (isolation, characterisation and pathogenesis) in Golden grey mullet in the Caspian Sea and study of pathogenecity and possibility of transmission to the other fish species (Sturgeon fishes, Rutilus frisii kutum and reared Rainbow trout and Carp) Viral Nervous Necrosis (VNN) is a worldwide disease affecting several species of cultured marine fish. For the past two decades, betanodavirus infections that cause Viral Nervous Necrosis (VNN) have emerged as major constraints on the culture and sea ranching of marine fish in almost all parts of the world. More than forty species mainly of marine origin have been so far affected and this number is likely to rise in future following the introduction of new species and the increase of aquaculture trade. Unknown acute mortality occurred in wild golden grey mullet Lisa auratus and Liza saliens in Iranian waters of Caspian Sea in recent years. In order to isolation and confirmation of causative agents of golden grey mullet mortality in the Caspian Sea, a complementary research investigation project was designed in 2005 and approved immediately in Iranian Fisheries Research Organization (IFRO). Many diagnostic aspects such as Virology (Cell culture and Elctereone Microscopy), Hemathology, Bacteriology, Histopathology, Molecular biology (NestedRT-PCR), Heavy metals measuerment and Serology (IFAT and IHC) were employed in mentioned multidiciplinary project. About 322 moribund fish samples which revealed skin darkening, erratic swimming behavior such as spiral and belly-up at rest and high distention of swimming bladder. Suspected samples were collected from coastal capture sites in iranian north proviences in 2006 till 2009. Targets tissue such as brain and eye were removed in strile condition and then kept in -80oC frezzer for cell culture and Nested-RT-PCR. Other tissue samples from liver, kidney, intestine, stomach, gill, skin and muscle, gall bladder and gonads were taken and fixed in 10% buffer formalin and same parts fixed in glutaraldehyde 3% for histopathology, IHC and EM respectively. Cytopathic effect (CPE) was observed in those cell cultures just six days after inoculation with the dilutions of the tested 312 homogenate supernatants. CPE in monolayers of cells cultured (SSN-1 cell line) was characterised by thin or rounded, refractile, granular cells with vacuoles. Nine samples were positive in virology assay. Nested- RT-PCR was done on suspected tissue samples and supernatant of CPE positive samples and 21 tissue samples and all CPE positive samples were positive. IFAT was selected as a confirmatory method for identifying viral strains replicating on cell cultures and carried out with rabbit anti-betanodavirus serum on suspected tissue samples and some smears of CPE positive samples. Some bright points approved betanodavirus antigen and confirmed cell culture and Nested-RT-PCR findings. In fixed tissue samples widespread and massive vacuolation were observed in brain, spinal cord, retina and optical nerve. In order to confirmation of diagnostic findings , IHC was done with monoclonal antibody antibetanodavirus and some red-brown points were observed. Theses findings revealed expected viral antigens and confirmed previous results. Moreover, virus particles with 25-30 nm in diameter were visualized in infected brain and retina using positive staining in TEM. Also pathogenicity test was employed to confirm the obtained results. So Guppy fish Poecilia reticulata and sturgeon fry were used instead of the experimental host due to ease of handling and susceptibility. After 15 days post infection, guppy bathed in VNN-infected tissue culture with 104 TCID50 showed clinical signs similar to naturally infected Golden grey mullet, and the mortality rate reached up to 100% in 75 dpi. When target organs were examined by cell culture isolation, serology, and histopathology, all revealed the presence of virus in the Guppy. Suspected supernatant injected to sturgeon fry through intravitreous injection and widespread vacuolation were observed in brain and spinal cord buy IHC and Real time PCR were negative. In conclusion, with attntion to obtained results in this investigation such as ecological factors, clinical signs, histopathological, virological and bacteriological results, molecular analysis, (IHC, IFAT, PCR), TEM demonstration, serological and hematological findings, it could be confirmed that VNNV was the main causative agent for disease outbreak in Golden grey mullet in Southern coastline of Caspian Sea