NEW TECHNOLOGIES IN AQUACULTURE DEVELOPMENT (JOURNAL OF FISHERIES)
Year:2017 | Volume:11 | Issue:1 |Papers Count:9

To survey on the effect of anti fungal extract of Thymus vulgaris and Origanu majorana on the Fuzarium sp., randomly from 30 Litopenaeus vannamei’ s brood stock of breeding center of Delvar Meigu in Bushehr province with 46± 0. 12 gram weight mean fungal samples from gill and skin surface were got and cultured on Potato dextrose agar medium and was transferred to Veterinary Medicine of Islamic Azad University, Kazerun branch. Fuzarium sp. base on key of Pé rez-Farfante and Kensley (1997) was identified by identification key and was cultured on Trypton soy broth again. Extraction was done by method of suspension in methanol 96%. The effect of antifungal of Extraction was examined by method of continuous concentration of extracts in to tube to determine MIC and MFC. To obtain the MIC of plant extracts, 8 extracts for each series (concentrations of 10 to 80%) of 12 test tubes were prepared. To determine MFC of transparent tube of MIC testing which the fungus had not grow on, the tubes were cultured on Sabouraud dextrose agar medium again. The results showed that the minimum inhibitory concentration (MIC) of Thymus vulgaris extract at concentration of 50, 60, 70 and 80 percent, were 8, 8, 4 and 2 respectively and the minimum inhibitory concentration (MIC) of the Origanu majorana extract in concentrations of 30, 40, 50, 60, 70 and 80 percent, were 16, 8, 4, 4, 2 and 0. 5 respectively. The minimum fungicidal concentration (MFC) of Thymus vulgaris extract at concentration of 50, 60, 70 and 80 percent were 16, 8, 8 and 4 respectively and the minimum fungicidal concentration (MFC) of Origanu majoranaextract at concentration of 40, 50, 60, 70 and 80 percent were 16, 16, 4, 4 and 4 respectively. There was a significant relationship between extract concentration of herbal drug and their effects (P≥ 0. 05).

In this study a total of 7 stations with different distances from each other were selected in the Ganjegan river, Kohgiluyeh and Boyer-Ahmad province, Iran. Determination of physicochemical properties and water nutrients was conducted every two months and over a one-year period. Maximum BOD5 was measured at station 7, which indicates that the amount of organics will be increased whatever we go from upstream to downstream farms and consequently the amount of consumed oxygen (BOD5). The minimum of phosphorus was measured in winter and in station 1 and the maximum amount of phosphorus was measured at the station 6 and in summer that is resulting from higher activity of farms and more feeding, mainly due to suitability and high water temperature in the warm seasons. Ammonium and nitrite in station 1 were at least level because there is no fish farming activities at the upstream. The maximum amount of TDS and TSS were measured in stations 6 and 7, which received all wastewater of upstream farms. Average phosphate (PO4) in stations 4, 5, 6 and 7 showed a significant difference with stations 1, 2 and 3. Station 6 had a higher NH4 compared to stations 1, 2 and 3, which may be due to short distance and activity of upstream farms. Nutrients in the effluent of fish farms can have a major role in physicochemical changes of water resources. Careful study of water resources in fish farming and awareness of the self-purification of water resources proportional to the flow rate, water temperature, floor slope and etc. is essential before issuing any permit for farm construction.

The Zyarat river which is the main source of surface water to supply water for city of Gorgan and its surrounding areas has been confronted with potable water quality deterioration problem in the recent years, therefore its management and water quality control has specific importance. The lithology of Zyarat river bed consists of limestone, marl, sand stone and collvial and alluvial deposits. In order to, investigate physiochemical parameters, sampling was conducted in 10 hydrometery stations (in Spring and Summer 2012) along the Zyarat river. At each sampling occasion BOD5, Cl, Ca, pH, NO3, PO4 and turbidity were measured. The results showed that physicochemical parameters in Zyarat river can be affected by its litology, transfer material that entire to it and some Human's activity like agriculture and urban activities, Also the best situation was related to first station in Khordad month and the worst situation was related to 3 station in Ordibehesht month. As for present results quality condition of Zyarat stream was unsuitable and the decision making process for reducing the pollutant of the Zyarat watershed can be facilitated by taking into consideration the results of this research given the time/budget constraints.

This study was conducted to examine the effect of dietary Inulin prebiotic on growth and body composition of rainbow trout. A basal diet supplemented with 0 (control), 1, 2 and 3 percent prebiotic to formulate four experimental diets. Each diet was randomly allocated to triplicate groups of fish with initial average weight of approximately 20. 57± 0. 78 g. After 60 days of feeding, final weight of fish fed with prebiotic was significantly higher than control group (P<0. 05). The feed conversion ratio (FCR) in fed treatment with prebiotic was significantly lower than control group which treatment contained the lowest amount of 3 percent. SGR with prebiotic was higher than control group (P<0. 05). The analysis of body composition suggested the amount of protein showed significant increasing to the control group and the highest amount was seen in treatment 1 and 2 percent. The fish fed 1 and 2 percent diet exhibited lower levels of lipid and the fish fed 2 percent diet exhibited lower levels of ash. The results suggest that administration of dietary Inulin at 2 percent exerted positive effects on growth and body composition in rainbow trout.

In order to study phytopague fingerlings feeding in fish ponds, simultaneously to the beginning of warm season and cultivation, fingerlings of 3-5 g from 4 ponds in Mazandaran and Golestan provinces were captured, fixed with formalin, then transferred to the plankton determination laboratory of the Caspian Sea Ecological Institute. In this study, were totally recorded 94 species of 5 phylums, including 30 species of Chlorophyta, 17 species of Cyanophyta, 34 species of Bacillariophyta, 9 species of Euglenophyta and 4 species of Pyrrophyta. Based on this study, Substantial differences in food digestion Silver Carp fingerlings based on the types of foods exist and the greatest difference was observed in the digestion of Bacillariophyta. Despite the abundance of phytoplankton density of Bacillariophyta, only 10% of the pool water formed of Bacillariophyta but the highest percentage of digestion, over 36 percentage of phytoplankton population contain Bacillariophyta. Also Bacillariophyta contain 56 percentage of beginning of digesting system and 20 percentage in the end of digesting system. Chlorophyta and Cyanophyta plug at the end of the intestine had a higher percentage than the beginning of the intestine and indicates that the industry is less digestible, while the branch Cyanophyta had the highest concentration in the water swimming pools (8442985 pcs per cubic meter). Pyrrophyta branch in the pool water at the rate of 11, 300 per cubic meter was observed, but in the gut of children studied fish species were found Pyrrophyta. Comparison of phytoplankton pool and intestinal contents with Chi-square test showed that the difference between the frequency difference between the frequency of phytoplankton phytoplankton pool and the beginning of the colon and intestinal contents at the beginning and end of the intestine showed no significant difference. Base on the results of this study we propose to make more studies on fertilization and the proportion of different fertilizers in fish ponds in order to obtain easily digestible phytoplankton thus increase in fish exploitation.

Haraz river of the most important rivers in the Southern Caspian Sea due to ecologically valuable species. For this purpose, the physical and chemical characteristics of this river were studied and the effect of Qezel Kaj trout farm effluents on water quality was assessed. Sampling was performed seasonally in 2014. Overall 4 stations were determined before and after the fish farm. The results of the analysis of water quality parameters showed that the station 3 (output of farm wastewater) the factors of sulfate, phosphate, nitrate, nitrite, total hardness, temperature and pH increased and oxygen content decreased, this indicating high pollution in this station. Compare of contamination between the stations surveyed showed that station 4 that was located immediately after farm output, further contamination compared to upstream stations and with distance from farm, the degree of water pollution was low. The results showed the station which after the field is the more pollution than the previous stations. Whatever distance from the farm, the river has a process of self-purification and degree of contamination of water decreases and eventually finally placed on the floor with higher quality.

Numerous attempts have been done to increase the aquatic products through the effects of various edible additives on the growth and reduction of mortality. The current study was carried out to evaluate the effect of different levels of Anato (Bixa orellana) seed powder on growth, survival and production rates of large shrimp (Macrobrachium rosenbergii). This study was carried out in four treatments and each treatment with three replications. Treatments included: (1) control (no Anato powder), (2) 50 mg/kg, (3) 150 mg/kg and (4) 200 mg/kg Anato powder. Shrimp were randomly divided into 12 fifty liter plastic tanks (20 shrimp per tank). Shrimps were fed 3% of body weight twice a day (at 9 and 17 o’ clock) for 8 weeks. Mean water temperature was 31 ± 1 ° C during study period. Results of this study showed that treatments were fed by Anato powder had a higher final weight, specific growth rate and higher protein efficiency than control group (P<0. 05). Treatments containing 150 and 200 mg/kg Anato had higher protein utilization index than control group (P<0. 05). Furthermore, treatments containing 150 and 200 mg/kg Anato had a higher specific growth rate and food conversion ratio than control group and 50 mg/kg Anato treatments (P<0. 05). There was no significant differences in survival rate between feeding treatments and control group (P<0. 05). Results of this study showed there was no significant difference in diets containing 150 and 200 mg/kg Anato (P<0. 05). Furthermore, fourth treatment (200 mg/kg Anato) can be as a suitable suggestion for large freshwater shrimp diet due to more favorable effects on the growth rate, reduction of feed conversion ratio and increase in production compared to treatment containing (150 mg/kg Anato).

In the present study, the physical and chemical parameters of water (pH, EC, TDS, TSS and TS) and the morphologic characteristics of sample (height, weight, age and gender), via accumulation of Cadmium in Cyprinus carpio muscles were investigated in Choghakhor wetland. Forty-five Cyprinus carpio were sampled by net and 45 water samples were taken from 3 stations, from Feb. 2015 to Jun. 2015. After acid digestion, the amount of Cadmium was measured by graphite furnace atomic absorption spectrometer and the data was analyzed by SVM method. The results show that the Cadmium residue in sample muscles is less than the maximum admissible rate by European Union (200 mg/l). However, since the accumulated rate of Cadmium is quite negligible in the muscles and less than its accumulation in other tissues, hence, the possibility of Cadmium concentration in liver and gill organs is much higher. Among the physical and chemical parameters of water, the EC, pH, TS, TSS and TDS are most effective in the rate of Cadmium absorption in Cyprinus carpio muscles, respectively. It is while in accordance with the descriptive analyses. Studied parameters have no effects on accumulation of Cadmium in the fish. Thus, in comparison with descriptive analyses, SVM and RSM methods are more reliable for evaluating the effect of physical and chemical parameters on accumulation rate of metals in the fish tissues in natural ecosystems.