Journal of Aquaculture Development
Year:2019 | Volume:13 | Issue:3 |Papers Count:10

This study was conducted to determine the effect of growth hormone on some growth and immunity parameters at three stages of rainbow trout eyed egg, alvine and fry. The experiment was carried out in 4 treatments with concentrations of 0, 0. 1, 0. 5 and 1 mg/l of somatotropin hormone. For permeability, different experimental groups were treated with sodium hypochlorite (0. 005 %) for 15 seconds before bathing with growth hormone; then they were immersed with different concentrations of growth hormone for 5 min. The specimens were then transferred to the tanks and were kept to 1. 5 grams of weight. The results showed that the lowest feed conversion ratio (0. 44) was observed at 0. 1 mg concentration of were immersed with growth hormone in the egg stage, followed by in the alvine and then in the fry stage. The highest feed conversion ratio (0. 59± 0. 007) was observed in control group. The specific growth factor was the highest amount in the treatment of 0. 1 egg stage (3. 77± 0. 77) and was significantly difference with control group (P<0. 05). The lowest specific growth factor (3. 33± 0. 1) was observed in the control group. The highest lysozyme activity (0. 0044 ± 0. 055005) was observed in 0. 1 and 0. 5 concentrations in fish exposed to hormone in the egg stage, which was significantly higher than other experimental treatments (P<0. 05). Also, the levels of immunoglobulin in fishes that were immersed with growth hormone in egg stage were significantly higher than other treatments (P<0. 05). The results showed that growth hormone had a better performance in rainbow trout egg stage than the alvine and fry stage.

This study was conducted to test the effect of bioremediation the polychaete worm Nereis diversicolor in order to removal of wastewater nutrition derived different densities Huso huso. The aim of this study was determination of different densities for creating the equivalence for rearing of N. diversicolor and H. huso rate in the integrated culture system. Three different densities of H. huso culture with N. diversicolor fed with fish feed waste were considered at water temperature 23° C for 8 weeks. The obtained results demonstrated that N. diversicolor could grow via feeding with the fish waste water. The pure production and survival rate of harvested Nereis in NWF2 treatment was significantly higher than other treatments (P<0. 05). The highest removal efficiency of waste water including NO2-N (91%), TSS (89%), BOD5 (85%), PO4-P (65%), total phosphorus (63%), total nitrogen (56%), NH3-N (35%), were seen in different treatments. The removal efficiency of waste water nutrition was decreased without use of N. diversicolor. Also, removal efficiency of NO3-N did not occur with presence of the worm. The obtained results demonstrated that increasing of worm growth, decreasing waste water nutrition and achieving of secondary production made system efficiency. The use of worm biomass as a waste treatment method could economically play important role.

Due to economic importance production of fish farms, in this research, the producers of cold water fish rainbow trout farms in the province in 2017 was evaluated using Super efficiency comprehensive analysis. In this regard, the information required to complete the questionnaire and paddy yield method based on a comprehensive analysis of the results obtained were compared with Super efficiency comprehensive analysis. In general, the results showed that the average level of technical efficiency in the model with constant returns to scale assumption (CCR) equivalent 81. 70% with a standard deviation of 0/258 in the range between 0. 23 to 0. 1 and only 3. 23% on fish farms are efficient, but not much inefficiency in other units. The mean level of technical efficiency of variable returns to scale model (BCC), equivalent 15. 92% SD 0. 126 in the range between 0. 55 to 0. 1, and 60% were fully functional. The results indicate that the average efficiency of the scale is 85. 31% and its range ranges from 0. 36 to 0. 1. As well as apparent differences in technical efficiency levels between the study areas are the most important cause of technical inefficiency in aquaculture has different way of managing. With regard to the results obtained with optimal management of inputs, the level of performance can be significantly increased. Keywords: Isfahan, Cold Water Fish, Dat

This study aimed to compare growth indices and production of rainbow trout breeders (Oncorhynchus mykiss) without any specific pathogens in various populations at the Fishery Research Center of Coldwater-Tonekabon. The project's implementation included collecting Pre-breeders were done in selected rainbow trout breeding centers (based on the approval of the Iranian Fisheries Organization and the Iranian Veterinary Organization) at the provinces of West Azerbaijan, Mazandaran, Kohgiluyeh and Barahi. In total, the rainbow trout (in the form of seven treatments and three replicates) were collected from seven farms in the above-mentioned provinces and cultured with a density of 10 kg / m2 in concrete ponds in accordance with the principles of biosecurity. Pre-breeders have been marked for growth traits in order to trace the economic traits of the growth. Biometry was done in different growth stages in order to measure biological parameters such as obesity coefficient (CF), specific growth rate (SGR), and calculate the relationship between length and weight. The feeding rate for three-year-old breeders was 2-3% of fish weight and three times a day. During the breeding period, all physical and chemical parameters of the water were monitored and evaluated in order to control the optimum growth conditions. Water change was also done 4-6 times a day to maintain the physical and chemical quality of water. The mean of the obesity index of rainbow trout among the seven farms at the end of the growth period indicated that the highest of the obesity coefficient in pre-breeders from the Genetic Research Center of Shahid Motahari Yasouj which was 1. 67. The growth equations showed the highest coefficient b (3. 15) in males fish from the field of Mr. Maroufi, which indicates that the growth is isometric. Since pre-breeders were in the same environmental conditions, the environmental variability resulting from changes in environmental conditions as well as the variance of interaction between genetics and the environment declined to zero. Obviously, in this case, the functional differences of growth indices among different populations are due to genetic function and genetic variance.

Increase in emergence of drug-resistant strains of microorganisms have necessitated finding natural compounds with antimicrobial properties and negligible side effects. Microalgae rich in active metabolites could be used in this branch of pharmaceutical industries. Chlorella vulgaris a microalgae was collected from the International Sturgeon Institute-Rasht-Iran. Antibacterial activities of hexane and ether extracts of C. vulgaris against gram-positive Micrococcus luteus and Gram-negative Aeromonas hydrophila bacteria were evaluated. When the required volume and cell concentration of algae under pure culture condition reached the hexane and ether extracts of the cells were obtained according to Cannell et al. (1988) antibacteria activities were examined using well diffusion methods (1). Hxane and ether extracts of C. vulgaris inhibited A. hydrophila and M. luteus bacteria. The diameter of inhibition zone of hexane extract against M. luteus and A. hydrophila, varied between 9. 3-11. 6 and 9. 6-11 mm while these diameters for ether extract varied between range 20. 3-25 and 7. 6-16 mm respectively. Gas chromatography mass spectrophotometry was used to identify different substances in diethyl ether and hexane extracts. The main substances in ether extract were ketone compounds, esters, hydrocarbons, siloxane, saylyl, terpenes and hydrvsaylyl polyesters. In hexane extract the main substances were hydrocarbons, siloxane, Saylyl and hydrvsaylyl are polyester. The inhibitory effect of ether extract was higher than the hexane extract thus it could be used as a solvent for extraction of antimicrobial compounds.

This paper intends to study the accumulation of copper oxide nanoparticles (CuO NPs) on hepatopancreas and muscle tissues in Shrimp L. vannamei. The CuO NPs were synthesized through chemical sequestration and were studied by precise techniques of FTIR, SEM, AFM, XRD, and DLS, and then their accumulation on L. vannamei were evaluated. In this research, the bioaccumulation of CuO particles on hepatopancreas and muscles tissues were studied after exposure to three concentrations (0. 25, 0. 5 and 1 mg/L) of CuO NPs. According to the findings of this study, the average copper concentrations in these three treatments (0. 25, 0. 5 and 1 mg/L) were 18. 676, 18. 585, and 18. 484 mg/Kg respectively in muscle tissues and in the same treatments of copper concentration in hepatopancreas tissues, were 15. 624, 15. 351 and 14. 250 mg/Kg, respectively. The results showed that copper concentration in muscles tissues was higher than in hepatopancreas tissues, in 1 mg/L treatment this difference was statistically significant (P˂ 0. 05). There was no much difference among copper concentrations in the muscle tissue and there was no significant differences. Increase of CuO NPs concentrations in different treatments was associated with decrease of copper concentrations in hepatopancreas tissue. Showing reverse correlation of these parameters (r=-0. 45, P˂ 0. 05). Therefore, according to the results of this study, the mean copper concentrations in these two tissues were lower than the standards of the World Health Organization, which may be considered as unlikely to endanger the human life.

Phytoplankton groups have specific role in the water quality of Neor Lake for living of fishes in Ardabil province. So, in order to study water quality and fish stocks assessment of Neor Lake after entering Carassius gibelio, primary products of this lake at first should be evaluated. This investigation carried out in 5 stations and 8 months during 2014. Phytoplankton sampled by 1 liter Ruttner. After that the sample fixed by formalin and after homogenizing the sample in laboratory, 5 milliliters of it precipitated for 24hr in order to further evaluation and enumeration by invert microscope 400X. According to the results, 6 phyla and 68 genera have been identified, mainly. Totally, 24, 25, 11, 2, 4, & 2 genus identified that belong to phyla Bacillariophyta, Chlorophyta, Cyanophyta, Pyrrophyta, Euglenophyta and Chrysophyta, respectively. The results show that stations 1 (Dareh Khersi) and 5 (Robero Mobish) have the most and least density of phytoplankton with annual mean of 132300500 ± 31011000 and 118575560 ± 45165997, respectively, compared to other stations. Station 3 (Mameli Dash) has the least phytoplankton density, 76071333 ± 20606342. Phyla Cyanophyta and Bacillariophyta especially genus Oscillatoria and Synedra were dominant in all stations. Commonly, in fall, the mean density of phytoplankton is more than other seasons and in winter it is at least. According to statistical analysis Kruskal Wallis, phytoplankton density show significant differences in different months and seasons of year (P<0. 05). However, there is no significant differences among stations (P>0. 05). Significant differences observed in density of phyla, too (P<0. 05). Generally, Neor Lake is eutrophic from nutrient material and phytoplankton density point of view after entering Carassius gibelio. The Carassius gibelio stock as the only fish of this ecosystem were 21. 9 2 tons in 2014.

This experiment was carried out to examine the effect of temperature on egg incubation period, exogenous feeding onset, growth and survival of the zebra cichlid, Cichlasoma nigrofasciatum larvae with two replications. Experiment was conducted in four groups of brood stocks with four temperatures with two replications 22-24 ° C, 24-26 ° C, 26-28 ° C and 28-30 ° C. After ovulation brood stocks were kept in aquariums until six hours and egg counting continued 12 hours after viewing the first larvae moving to determine the final number of larvae. Larval rearing was conducted over four months and at the end resulted data were statistically analyzed. Results showed that although the highest percentage of weight gain, daily growth rate and specific growth rate related to the highest thermal treatment (group D) but also the highest percentage of hatching and larvae survival rates observed in group C with a temperature of 28-26 ° C treatment so the temperature has been important effect on hatching time, duration of yolk sac absorption, growth factors and survival of zebra cichlid larvae so that increasing of temperature increased growth and reducing the time of hatching and exogenous feeding onset. Statistical analysis showed that there is a significant relationship between the temperature and duration of hatching, temperature and duration of yolk sac absorption and temperature and efficiency of growth and temperature and survival the larvae. The fastest start of feeding was in Group A, the highest percentage of hatching, survival rate and lowest level of Corruption eggs were in Group C. Thus, since that the highest percentage of hatching, lowest level of Corruption eggs and highest of the fish larvae survival occurred at the temperature of 28-260C, seems to be this temperature the best temperature for Cichlasoma nigrofasciatum reproduction.

The present research was designed to evaluate the effects of inactivated Spot White Virus with radiation (gamma irradiant WSSV) on survival rate and immunity factors (THC, TPP, PO, SOD, POD) of white leg shrimp. The experiment was done in Bandar Imam Khomeini hatcheries from November 2013 until February 2014. In this study, the survival rate and immunological parameters of shrimp that exposed to inactivated Spot White Virus with radiation were compared with the control group. Based on the challenge test results, the vaccinated shrimp had a higher survival rate than the control group. Results indicated that survival rate and immune parameters such as total hemocyte count (THC), total protein plasma (TPP), superoxide dismutase (SOD) activity, peroxidase activity (POD) and phenoloxidase activity (PO) were higher than the control groups. Also the immunity factors increased during the period from day 1 to day 25 significantly. Therefore, this experiment concluded that gamma irradiant WSSV is effective immunostimulants in white leg shrimp Litopenaeus Vannamei.

The main objective of this study was to determine the effects of diets containing 0, 2. 5, 7. 5% Spirulina platens is meal on growth performance, survival rate, skin pigmentation and digestibility of carotenoids in Oscar fish (Astronotus ocellatus). 288 Oscar fish with mean body weight of 10. 73± 0. 09 randomly divided in to 24 aquariums with 45 liters’ water capacity. The experimental treatments were 0, 2. 5, 5 and 7. 5% Spirulina in diet. Fish fed 42 days by experimental diets. To maintain water quality siphoning and water change performed daily and water quality parameters measured weekly. The results showed adding Spirulina in diet showed no significant effect on growth performance, feed efficiency and survival of Oscar fish (P>0. 05). Carotenoid digestibility was high in all treatments (>97%) and there was no significant difference between 7. 5% Spirulina and control group (P>0. 05). The highest skin carotenoid content was observed in fishes fed with 7. 5 Spirulina in their diet (P<0. 05). By respect to significant increase in body pigmentation, the present results demonstrated that 7. 5% S. platensis meal can a suitable dietary level used in Oscar fish diet.