Study of anaesthetic effects of clove oil (Eugenia caryophyllata) in common carp (Cyprinus carpio) under various pH and temperature condition

The anaesthetic effects of clove oil in juvenile common carp (8-12 g) were investigated under various water quality conditions, consisting of different pH and temperature. The time to loss the equilibrium, induction of anesthesia, equilibrium recovery and response recovery were measured. The results showed that clove oil induced the desirable anaesthetic condition in less than 3 minutes in all experiments. However the time of equilibrium recovery and response recovery were longer than 5 minutes in many cases. When using clove oil at concentration of 100ppm, the most suitable anaesthetic effects and recovery times were observed at water temperature of 25֯ C and pH=7 and 8,as well as at 30֯ C with pH=9. No morbidity or mortality occurred during induction of anesthesia by clove oil and recovery of fishes

Histological study of liver and pancreas in adult Otolithes ruber in Bushehr, Iran

In this study, the digestive systems of 10 adult Otolithes ruber specimens from Bushehr province water, south-west Iran were removed and the livers and pancreases were fixed in formalin 10%. The routine procedures of preparation of tissues were followed and the paraffin blocks were cut at 6 microns, stained with H&E and studied under light microscope. The results of microscopic studies showed that liver as the largest accessory organ surrounds the pancreatic tissue in the fish. Liver was found to be a lobulated organ encircling the pancreas among its lobules. Hepatic tissue of the fish was found to be similar to many other bony fishes. Hepatocytes included glycogen and fat vacuoles that located around the hepatic sinusoids. Pancreas as a mixed gland microscopically, was composed of lobules consisting of serous acini (exocrine portion) and langerhans islets (endocrine portion). Pancreatic lobules are usually found as two rows of acini which a large blood vessel located in between

Safety evaluation of chloramine-T on ornamental zebra fish (Danio rerio) using LC50 calculation and organ pathology

The need of aquarists for proper and safe disinfection of fish with Chloramine-T (CL-T) necessitates toxico/pathologic examinations. This study assays toxicity level of CL-T and histopathologic changes of gills, liver, kidney and brain of treated zebrafish (Danio rerio). Groups of 10 Zebrafish were treated with 0 (control), 5, 10, 15, 30, 50, 100 and 200 mg/L of CL-T. Mortality was recorded at every 6 hours until 96h after the beginning of the treatment and lethal concentration for 50% of population (LC50 at 24h and 96h) was calculated. The histopathologic samples were taken from dying fish during the exposure period. Histopathological changes were not evident in organs of the control group. In the gills of treatment groups, congestion, edema, separation of epithelium of secondary lamella from basal membrane, fusion and hypertrophy of secondary lamella, telangiectasis and necrosis of lamella epithelium were observed. In the liver of treatment groups degenerative changes and necrosis of hepatocytes were visible. The kidney samples represented hydropic degeneration, necrosis, dilation of periglomerular urinary space and hyaline droplets in renal tubules in high concentration. The brain of treatment groups showed spongiosis and increase in glial cells. Severity of these lesions was related to the concentration of CL-T. LC50 24h for CL-T was 428.649 mg/L and LC50 96h was 11.044 mg/L which reveals the low level of toxicity for few hours of treatment. The concentrations below 15mg/L are reasonably safe and recommended for usage in D. rerio treatment during 24h of bath

Effect of hypoxia, normoxia and hyperoxia conditions on gill histopathology in two weight groups of beluga (Huso huso)

The influence of dissolved oxygen concentration on gill histopathology of great sturgeon (Huso huso) was evaluated in two weight classes (initial weight 280.9±49.2 g and 1217.9±138.1 g respectively). Oxygen treatments included hypoxia (2-3 mg/l), normoxia (5-6 mg/l) and hyperoxia (9-10 mg/l). The fish were acclimated to experimental tanks for one week then randomly distributed into 9 tanks in each of the initial weight classes (3 and 6 fish per tank in higher and lower initial weight classes respectively) for 8 weeks. In order to find the histopathological changes, gill samples were collected, dehydrated through ethanol series, embedded in paraffin , sectioned at 7 µm thickness using a Leitz microtome and stained with H & E. No mortality was observed over the 8 weeks of the experimental period. There were significant differences in weight and feed intake between treatments in the both weight classes (P<0.05). Fork length showed significant differences in lower initial weight class (P<0.05). The main histopathological changes were observed in gills including: Hyperplasia, loss of secondary lamellae, hemorrhage and congestion in primary and secondary lamellae, lamellar fusion, epithelial lifting in secondary lamellae, clubbing of secondary lamellae, telangiectases, increase in melanin pigments and numerous vacuoles in primary and secondary lamellae (in hyperoxia treatment). All these lesions may reduce gill functional surface of gaseous exchange, impairing respiratory function

Infection of skipjack tuna Katsuwonus pelamis (Linnaeus 1758) of Oman Sea with cestode Trypanorhyncha (Diesing 1863)

Numerous reports on existence of white cysts in musculature of skipjack tuna Katsuwonus pelamis and lack of information about the quality of cysts and individual responses of fish to them led the authors to focus on this fish as a commercially valuable species. This study investigated the histopathologic responses of skipjack tuna to highly prevalent cystic larval stages of Trypanorhyncha. Some 92.25% of 400 examined skipjack tuna of Oman Sea (Iran) captured from processing center in Chabahar have been diagnosed infected by Trypanorhyncha Larvae through gross muscle examination. Minimum of 5 to maximum of 19 cysts were observed per each flank flesh with no significant difference between number of cysts from right (9 ± 4) and left flanks (10 ± 4) and also males and females (p>.05, t- student test (spss version 16)). Using hematoxylin and eosin (H&E) staining of 4µm sections of surrounded cysts with muscle and light microscopy observations each metacestode was distinguished encapsulated by surrounding fibrous cyst wall consists of thin inner layer and a thick outer layer with the minimal histopathologic changes around it. The highly prevalent Trypanorhyncha infection in Oman Sea represents the high rate of infection among elasmobranches. The ability of encapsulated parasite to escape from the immune system of the host is assumed as one reason for the observed minimal tissue response in infected fish and the continuation of infection among elasmobranches and teleosts of Omen Sea

Molecular identification of some causative agents of streptococcosis isolated in farmed rainbow trout (Oncorhynchus mykiss, walbaum) in Iran

Streptococcosis is an acute infectious disease that causes mortality in marine and freshwater aquacultures. One of the most important hosts is susceptible to the disease of rainbow trout and during the past decade its industrial production has been growing in Iran. According to FAO, Iran is among the 10 countries producing fish in the world. The most important bacteria causing Strptococcosis includes Strptococcus, Vagococcus and Enterococcus genera. But in all cases, the clinical sings are the same. More than a decade has passed since the first report of this disease in Iran and unfortunately, this disease has become the most important problems of trout production in Iran. Therefor, 72 farms were selected in 8 provinces including Mazandaran, Gilan, Lorestan, CharmahalBakhtiyari, Fars, Kermanshah, Tehran and Kokiloye-Boyer Ahmad and a total 520 moribund and apparently healthy rainbow trout (weight 50 – 200gr) were collected during summer 2008 to 2009. Fish kidney, spleen and liver samples were culture aseptically and finally 206 isolates were identified as gram positive cocci. Using conventional biochemical test, S.uberis, S.agalactiae, S.dysgalactiae, S.faecium and S.inia. Additionally, 172 from 206 isolates were confirmed as S.uberis، S.agalactiae، S.dysgalactiae، S.faecium and S.inia using a PCR assay ased on the results, the most prevalent is belong to S.uberis (isolated from 5 of 7 province), S.dysgalactiae (isolated from 4 of 7 province), S.agalactiae (isolated from 2 of 7 province) and S.faecium and S.inia (from 1 of 7 province) respectively. It is necessary to mention, S.inia was identified just to Fars and any gram positive cocci was isolated from Tehran

Multidimensional Facets of Perceived Risk in Mobile Travel Booking

Despite the growing prevalence of smartphones in daily life and travel context, travellers still perceive an extent of risk associated with using their smartphone to book travel products. In order to alleviate or reduce perceived risk, it is important to better understand the dimensions of and the factors that contribute to perceived risk. This study analysed 411 responses from an online panel to examine perceived risk in mobile travel booking and identified the following facets: time risk, financial risk, performance risk, privacy/security risk, psychological risk, physical risk, and device risk. Several antecedents of perceived risk were identified. Perceived collection of personal information via smartphones contributes positively, while consumer innovativeness, trust, and visibility contribute negatively to perceived risk. Further, the predictive validity of perceived risk is confirmed as it significantly explains perceived usefulness, attitude, and behavioural intention in mobile travel booking. Implications to manage perceived risk and its antecedents are provided

Monitoring and identification of viral pathogens in SPF (Specific Pathogen Free) shrimp production project

Shrimp aquaculture has developed rapidly in 1980s decade and this development caused to increase shrimp diseases in farms. In the last 0f 1980s and first of 1990s find of health shrimp Postlarvae for stocking was hard. In Iran also after two decades diseases are the main problems, then a national project (Shrimp SPF production) was performed that this section was monitoring and identification of viral pathogens in that project. For this propose selected shrimps in farms was sampled and screened for main viruses (OIE list), shrimps without infection bring to quarantine system for one month and in the end of quarantine period were screened again. Then in winter spending, before and after spawning, it’s offspring in F1 and F2 also screened for viral pathogens by IQ2000 kit in Iranian veterinary organization lab. Moreover all shrimp feeds in clouding: fresh feed, live feed and pellet feed had been screened for OIE viral pathogens listed for three years. Results of viruses screening in shrimp sampled in all stages of project and feed that use in this project were negative. This project (SPF shrimp production in IRAN) performed successfully, we think this success relate to biosecurity system that were influence in this project

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

Comparison of neutral anolyte solution and malachite green efficiency on fungal contamination control of rainbow trout (Oncorhynchus mykiss) eggs in incubation stage

One of the important problems in Rainbow trout production industry is egg fungal infection especially saprolegniasis which is the most important mortality factor in Rainbow trout hatcheries. Controlling saprolegniasis in hatcheries was done using green malachite in the past years, which is a very effective fungicide. Nowadays, due to the prohibition of using green malachite, effort is done to replace it with other materials as an effective fungicide. Some of the most important materials which have been examined are formalin, sodium chloride and hydrogen peroxide etc. The aim of this study was to evaluate the effects of neutral anolyte on the mortality percent of rainbow trout eggs and produced larvae in point of view of growth indices and survival until yolk sac absorption and larvae active feeding in incubation phase comparing with green malachite to be able to introduce a suitable alternative. This study was carried out in a complete randomly plan with 7 treatments and 3 replications (21 troughs in general), in 20*35*70 cm (length*width*depth) Californian troughs containing an incubator. Treatments included anolyte solutions constant bathing with 0.5 and 0.25 ppm concentrations and periodic anolyte treatments with 2 ppm concentrations (every 2 days), positive control infected with fungus without any disinfectant and negative control without any infection or disinfectant. 300 grams of newly propagated green eggs of rainbow trout which were provided from one of the fish hatcheries in Haraz Road and acclimated with the trough’s water temperature, were distributed in one layer at the bottom of the trough basket. All treatments, except negative control, were infected with saprolegnia, taken from infected eggs of rainbow trout which were previously provided from one of the fish hatcheries of 2000 Road in Tonekabon. The treatments took one month to complete. The studied variables included hatching percent, percent of eyed eggs, abnormality percent and percent of unfertilized eggs, from which percent of eyed eggs was calculated and recorded in the middle and the rest of the variables at the end of the test. In this study Paired-sample T-student test, Levene’s test, one-way ANOVA and Bonferroni’s test was used. For examining egg abnormality, hatching, fungus infection and eyed eggs, first the percent of the variables were specified and then for comparing the rate of abnormality in one of the anolyte treatments (which had the least abnormality) and green malachite, Mann-Whitney test was carried out. This comparison was done to analyze the rate of hatching, fungus infections, eyed eggs, resulting from the materials used in different treatments, using one-way ANOVA Bonferroni’s tests. Results showed that in lower anolyte concentrations (0.5 and 0.25 ppm), the number of fungal colonies of hatchery water and the percent of egg fungus infection were significantly higher than higher concentrations of anolyte (100 ppm and 30 ppm) and green malachite. In other words with concentration increase, the fungicidal effect has also increased. In evaluating the percent of eyed eggs, statistical results showed that eyed eggs percent in 0.25 ppm treatment and green malachite treatment were significantly higher than the other three anolyte treatments. This result can explain egg hatching in 0.25 ppm concentrations and not seeing hatching in the (other) remaining three doses. Between the treatments of 0.25 ppm and green malachite, the group of 0.25 ppm anolyte can be a better disinfectant for rainbow trout eggs compared to green malachite, for fish farmers, due to the high percent of eyed eggs and the low total count of fungus. The results of this study showed that the amount of abnormality in 0.25 ppm treatment has been higher compared to the green malachite group. Because this study was the first research on using anolyte as a fungicide in rainbow trout hatcheries, therefore for more specific study of the concentrations, the timing of usage and the factors affecting these two, more vast and general research is needed