Comparison of four RNA isolating methods for identification of spring viraemia of carp virus (SVCV)

Spring viraemia of carp virus (SVCV), a negative sense single stranded RNA virus of the family Rhabdoviridae, is the causative agent of a highly contagious SVC disease that primarily affects the common carp (Cyprinus carpio), an economically important fresh water fish species with world-wide distribution.SVCV has also been reported to cause disease in other fishes such as Poeciliidae, Esocida , Centrarchidae , Siluridae and salmonidae . There are several diagnostic tests for the detection of SVC virus,however, the tests have not been validated. The reverse transcriptase – polymerase chain reaction (RT-PCR) techniques have been developed and validated representing a powerful tool for detection of RNA. One of the most important aspects isolating RNA is to prevent degradation of the RNA during the isolation procedure. In this study, we explored the efficiency of protocols for RNA isolation from the SVCV strain 56/70. For RNA isolation, we compared four protocols, two guanidine isotiocyanate phenol – chloroform based protocols (RNX – Plus Iran, Iq2000 kit Taiwan) and two column based protocols (Cinnapure RNA Iran, high pure viral RNA kit, Roche Germany) that were commercially available. The results showed that the column based protocols, Roche method and Cinapure performed better than other methods with the yields of 31.76 ng/µl, 16/21 ng/µl, respectively. Each protocol yielded good quality of total RNA bands (480 bp) being observed in agarose gel electrophoreses but was not observed in IQ2000 kit. Amount of total RNA isolated was lower for IQ2000 kit Protocol. Further, the RNA being extracted from SVC by column based protocol method were resulted in successful amplified using RT-PCR method

Identification of myxozoa and protozoa parasites of Barboid fishes of water resources in Khouzestan Province

A survey on parasitic infection of Barboid fishes of Khouzestan Province in southwest Iran was conducted from spring 2002 to autumn 2004. A total of 296 specimens from five fish species were examined. The specimens were collected from five stations including Ahwaz, Golestan, Mollasani and Dez Reservoir on Karoun River and Hamidieh Reservoir and Shadegan Lagoon on Karkheh River. The fishes were transported alive to the laboratory where they measured and weighed and then killed by cutting their spinal cord. Eleven parasites were separated of which seven were identified to the species level and four to the genus level. Of the protozoans we found Ichlyophthirius multifiliis, Trichodina sp., Goussia v., Balantidium sp. and of the myxozoans we observed Myxobolus persicus, Mkaruni, M nodulointestinalis, Miranicus! Mmesopotamia, Myxobolus sp., Myxidium rhodei and Myxidium pfiefferi. We reported three new parasites and eleven new hosts for Iranian freshwater fishes and three new hosts for three Myzoxoans

Cooperative Control of Multi-Master-Slave Islanded Microgrid with Power Quality Enhancement Based on Conservative Power Theory

Made available in DSpace on 2018-11-26T16:04:54Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-07-01Cooperative control of power converters in a microgrid offers power quality enhancement at sensitive load buses. Such cooperation is particularly important in the presence of reactive, nonlinear, and unbalanced loads. In this paper, a multi-master-slave-based control of distributed generators interface converters in a three-phase four-wire islanded microgrid using the conservative power theory (CPT) is proposed. Inverters located in close proximity operate as a group in master- salve mode. Slaves inject the available energy and compensate selectively unwanted current components of local loads with the secondary effect of having enhanced voltage waveforms while masters share the remaining load power autonomously with distant groups using frequency droop. The close proximity makes it practical for control signals to be communicated between inverters in one group with the potential to provide rapid load sharing response for mitigation of undesirable current components. Since each primary source has its own constraints, a supervisory control is considered for each group to determine convenient sharing factors. The CPT decompositions provide decoupled current and power references in abc-frame, resulting in a selective control strategy able to share each current component with desired percentage among the microgrid inverters. Simulation results are presented to demonstrate the effectiveness of the proposed method.Colorado Sch Mines, Dept EECS, Golden, CO 80401 USAAalborg Univ, Dept Energy Technol, DK-9220 Aalborg, DenmarkPetr Inst, Dept Elect Engn, Abu Dhabi 2533, U Arab Emirate

Modeling the rheological properties of highly nano-filled polymers

Organic and inorganic materials are usually added to polymers in order to achieve some benefits such as reducing the product cost, as well as achieving higher modulus and strength. Addition of these materials would change polymers’ behavior. Adding nano-materials to polymers on the other hand is a new challenge in the field of polymer composites where previous studies were unable to achieve good correlation with nano-composites at higher particle volume fractions. In this research, Yamamoto network theory is developed to investigate the behavior of highly nano-filled systems. For this purpose, five different types of sub-chain and two types of junctions are considered and the effect of particle size, concentration, and the model parameters in association with the behavior of the junctions are studied. Moreover, some experiments are performed on polystyrene filled with nano-silica at different particle size and concentration values in frequency mod in the linear region. At last, we compared the results of our final model with the experiments in order to evaluate its accuracy, which confirmed a very good agreement. © 2016, © The Author(s) 2016

Isolation and identification of bacterial and fungal microflora from Litopenaeus vannamei in Choibdeh, Abadan

Bacterial and fungal microflora of Litopenaeus vannamei cultured in Choibdeh, Abadan was studied. For this purpose, PLs before and after stocking and those shrimps persisting on food tray from June to August, 2006 were taken randomly. Live samples transferred to microbiology laboratory of South Aquaculture Research Center, Ahwaz. Special culture media (e.g. Tryptic Soy Agar + 1.5-2% Nacl & Sabouraud Dextrose Agar + 1.5-2% Nacl) were used for bacterial and fungal culture. We isolated 10 bacterial species of which Vibrio alginolyticus (36.92%) had high abundance among bacterial species. We also isolated and identified three fungal species including Aspergillus niger (66.66%) A. fumigatus (16.66%) and Fusarium sp. (16.66%). A. niger was predominant among fungal species. All bacterial and fungal species that were identified were opportunistic

Evaluation of the immunity factors (THC, TPP, PO, SOD, POD) of shrimp fed with the yeast Saccharomyces cerevisiae compared to shrimp fed without yeast

Effects of S. cerevisiae on immune parameters of the L. vannamei after 14 days of S .cerevisiae feeding were evaluated in this study. For this purpose a total of 300 pieces of shrimp with an average weight of 30 to 35 grams were selected from a pool shrimp Abadan CHOEBDEH. After making sure the health, absence of necrosis on the surface of the body, cuts antenna, shrimp were transferred to the center of BANDAR IMAM Research Station. Adaptation was carried out for 3-5 days. After the adaptation, shrimps were screened for virus (WSSV, TSV, MBV, HPV, YHV, BP, IHHNV and IMNV) and vibrio bacteria. After screening shrimps divided to two groups with three replication (including 50 pieces of shrimp in triplicate). The experimental diet has the commercial shrimp composition, but 2 g of S. cerevisiae substituted 2 g of fish meal. Shrimp of first group (T1) for 14 days with food containing nutritional yeast and shrimp in second group (T2) were fed with normal diet without yeast. After 14 days Immune Factors and survival rates in both groups were evaluated. The results showed that the relative survival rate between the two groups showed no significant difference. But Immune Factors (THC, TPP, PO, POD and SOD) in the treatment fed yeast (T1) compared to control treatment (T2) showed a significant increase. In conclusion these results suggest that the increased survival rate and resistance of shrimp after S. cerevisiae consumption occurs through immune modifications, such as increases in THC, TPP, SOD, SOP and PO activity

Evaluation of the immunity factors (THC, TPP, PO, SOD, POD) of shrimp fed with the algae Gracilaria corticata compared to shrimp fed without algae and exposed to white spot virus

White spot disease (WSD) is one of the shrimp deadliest viral diseases that causes heavy losses on all shrimp of Penaeid family. Most invertebrates are lacking adaptive immune system and its defense is the innate immune system that is as cellular and humoral, but a like immune system against white spot virus in shrimp was been detected. In this research, control and prevention of white spot disease in shrimp using algae Gracilaria corticata, investigated. About 300 vannamei shrimp were divided to 4 groups and fed by normal pellet and algae extract in 14 days. At the end of the fourteenth day half of the shrimp were challenged with acute white spot virus. After the fourteenth day in the days 0, 3, 9, 18 and 25 sampling were done from the hemolymph of survived shrimps and survival and immune factors were evaluated. Based on results, in the challenge test, shrimps that fed with algae extract has a significant survival rate than shrimp fed with commercial diet. Increased the Immune Factors from day one to day 25 observed during the test. Greatest amount of Immune Factors THC, TPP, SOD, POD and PO in T1 group were observed in day 25 of tests. This situation was also true for group2 (T2), but its rate significantly was less than group 1(T1)

Ecological study on rearing shrimp ponds (Litopenaeus vannemei) in Choebdeh Abadan

Following to introduce Vannamei shrimp (Litopenaeus vannamei) into Iran aquaculture industries by fisheries organization its postlarvae were successfully reared in ponds in Bushehr and Choebdeh in Khuzestan. Due to activity of Shrimp site and importance of input and output water quality, this study was done in 11 stations including: two stations in Bahmanshir river, two station in C4 and C5 irrigation canals, six staions in active farms along C4 cannel (Yonesi, Mosavei and Salman Zadeh), and C5 cannel (Mohamadi, Khairi and Ashraf Por) and one staion in output draing were selected. Sampling were carried out from May2009 befor beginning stocking to harvest time in October 2009. Physico- chemical parameters and plankton sampled biweekly and benthic animals and heavy metals were sampled monthly. Some parameters such as pH and temperature by using portable multy parameters and others. Analyzed with standard methods. Heavy metals were measured by plarography method (797 Vamtro). Plankton and benthos samples were studied only in Bahmanshir station. According to results the maximum values for DO (11.1 ppm) PO4 (1.86 ppm) NO3 (8.4 ppm) and TSS (4992 ppm), pH (8.4) NO2 (0.18 ppm) BOD5 (9.06 ppm) were measured. In comparison to aquaculture water quality standards except for TSS in river stations others are located in allowable range. We didn’t observed any main changes in water quality from river to output drainage. The results of biotic parameters in river stations showed that diatoms were the most group of phytoplanktons. Zooplankton groups were Copepods, Rotifera and Protozoa. Tintinids and Nematoda larvae were the most abundant zooplankton. Benthic animals were included nine crustacean species and two annelid species. Isopods with 52% were the most and ant group

Growth and survival rates, mean weight, food conversion ratio and total harvest in cultured Shrimp Litopenaeus vannamei in Iran

To introduce Litopenaeus vannamei to Iran as a cultured shrimp species, a experimental study was carried out to assess the effects of different stocking densities on growth rate, mean weight, survival rate, food conversion ratio and the total harvest of L. vannamei. Mee post-larval groups (P1,12) of L. vannamei (pond A: 20 PL/m2, pond B: 30 PL/m2 and pond C: 50 PL/m2) with average size 0.9cm and initial mean weight 0.01±0.005g were used in this study. The experiments were carried out in three replications in 9 earthen ponds each half a hectare in size in Khouzestan province, south of Iran during 110 days. The result showed there was no significant correlation (P>0.05) between stocking density and survival rate in the semi intensive culture condition. Mean survival rate among farms were greatest at the lowest density, where mean survival in pond A, B, and C was 88.6%, 83.3%, 73.3%, respectively but the differences were not significant (P>0.05). The results also showed there was no significant relationship (P>0.05) between growth rate and growth days in each experiment. The mean growth rate/days for ponds A, B, and C were calculated at 0.16g/day, 0.16g/day and 0.15g/day, respectively. The food conversion ratio in the end of the study period for ponds A, B and C was 1.01, 1.17 and 1.2, respectively. Shrimp production increased with an increase in stocking density when farm production at Pond A and B indicated a significant difference (P<0.05) compared to that of the pond C. The total shrimp production for ponds A, B and C was calculated at 2803kg/ha, 3146kg/ha and 3972kg/ha, respectively. The water temperature ranged between 28±3°C to 23±3°C, with the highest in July and lowest in September. Salinity ranged between 25±2ppt to 12±3ppt, pH ranged between 8.6±0.2 to 7.50.4 and dissolved oxygen ranged between 5.8± 0.4ppm to 5.3±0.3ppm throughout the study. The study proved that L. vannamei could adapt to common conditions in Iranian shrimp culture environment and also we showed that the species production was higher than the native species already under culture

A study on immunological factors in white spot vaccinated shrimp, Litopenaeus vannamei in comparison to none vaccinated groups

The aim of this study was to evaluate the efficacy of white spot virus vaccine produced by gamma irradiation in the face of Litopenaeus vannamei in comparison with Gracilaria corticata and Saccharomyces cerevisiae Seven hundred and twenty healthy shrimp SPF L. vannamei subadult with average weight of 10±1.02 g were collected and divided into 8 groups. The first group (T1) was fed with commercial pellet as control. The second group (T2) was fed with S. cerevisiae added to shrimp feed (1 g/Kg), the third group (T3) G. corticata so that algae Gracilaria were dried and added to shrimp feed at the rate of 1500 mg per kg and finally, the fourth group (T4) was vaccination group which the shrimp were exposed to the vaccine and injected intramuscularly gamma irradiant WSSV (1µl/gbw) for 10 days. The shrimps of all groups were then injected with WSSV and maintained for 25 days. Results indicated that the survival rates for groups T4, T3 T2 and T1 were 57.05±3.52%, 22.5±0.5%, 15±1.05% and 00.0±0%, respectively. Ultimately, at the end of the study the shrimp group T4 showed higher hematological data: THC, TPP, SOD, POD and PO. The study concluded that gamma irradiant WSSV is effective immunostimulants in shrimp L. vannamei and the immunity has better performances than those of the G. corticata and S. cerevisiae