Journal of Aquaculture Development
Year:2019 | Volume:13 | Issue:2 |Papers Count:10

Vitamins are organic compounds complex and have the vital importance for fish and lack of them led to severe disorders in body. Different Levels of the vitamin C at type L-ascorbyl 2-polyphosphate including: lack of vitamin C (Treatment 1), 100 mg/kg vitamin C (Treatment 2), 200 mg/kg vitamin C (Treatment 3), 400 mg/kg vitamin C (Treatment 4), 800 mg/kg vitamin C (Treatment 5), 1600 mg/kg vitamin C (Treatment 6) in triplicate and grown for 8 weeks were considered in the Siberian sturgeon. Fish were considered for testing the oxygen tension and temperature. In each treatment, 18 fish were randomly marked inside the aquarium and were transferred separately after 4 hours for measuring of oxygen tension (Hypoxia 1-1/5 Mg / L, Nrmvksy 7-8 Mg / L, Hyperoxia 19-20 Mg / L) and thermal stress (temperature 10-11° C, the normal temperature of 22-24° C, 30-31° C and high temperature) in the fish to determine the effects of stress on cortisol and blood glucose levels. The results of this study showed a significant difference levels of vitamin C at different conditions of temperature and oxygen on cortisol with increasing the amount of vitamin C levels in all treatments. Cortisol levels were decreased in fish exposed to stress. However, the High oxygen tension differences, except for the amount of glucose showed significant difference at various levels of vitamin C and showed significant difference at the tension in the cases rapidity. However, with increasing levels of vitamin C, glucose consumption was lower than in control, and these results suggest that increase in the amount of vitamin C in compared to control fish showed better resistance against stress conditions and according to these results it can be concluded that high doses of vitamin C can reduce the effects of stress and play a positive role in Siberian sturgeon health.

To check the ability of guppy fish (Poecilia reticulata) to receive high dietary doses of oxymetholone hormone and its effects on growth parameters, survival and reproduction, 300 fish at the age of 10 weeks, with an average weight of 0. 38 ± 0. 09 g were randomly assigned to 5 treatments and 3 replications in 15 glass aquaria (100 liters volume). Hormone levels were considered as 5 different doses of zero (OM0), 100 (OM100), 200 (OM200), 400 (OM400) and 800 (OM800) mg per kg diet. The duration of study was 90 days and biometry was performed every two weeks interval. The result showed that with increasing levels of dietary hormone, final weight, specific growth rate and weight gain were not significantly changed (p>0. 05), but feed conversion ratio was significantly different between treatments (p<0. 05), so that the lowest and highest feed conversion ratio were obtained in control group (OM0) and maximum dose of hormone (OM800), respectively. By increasing the hormone dose, survival rate and breeding were significantly decreased (p<0. 05), so that the highest and lowest mortality rates were seen in the maximum dose of hormone (OM800) and control group (OM0), respectively. The minimum and maximum breeding were seen in the maximum dose of hormone and control group, respectively. The results showed that high doses of oxymetholone in the diet did not improve growth characteristics in fish and by increasing the dose of hormone, survival rate and breeding were significantly decreased.

The present research which aimed at identifying the effects of astaxanthin pigment in upgrading efficiency in producing goldfish larvae through 4 treatments and 3 replications was conducted in the winter of 2014. For this reason, a sum of 12, 4m3fiber glass fish ponds were prepared where in each, 50 female goldfish breeders were introduced with an average body weight of 47. 21± 2. 19g. Then, 4 diets containing zero level, 50, 100, and 150mg/k of astaxanthin were formulated and given to the fish for a period of three months based on 5% of their biomass. In late march of 2015, the female fish in each pond were individually fertilized with male fish that were only fed with the control diet. All the biological characteristics of female breeders were examined. In addition, at larval rearing stage, the larvae produced in each treatment were kept at separate tanks and larval variations in terms of yolk sac absorption, condition factor and larval survivability were checked across different treatments. Meanwhile, qualities such as larval morphology, notochord length, body depth, yolk sac surface area, both prior and after absorption were determined and contrasted. The results obtained in this research showed that the diets containing 150mg/k astaxanthin brought about a superior impact on the reproductive qualities of female goldfish breeders, the eggs as well as the larvae. The hatched eggs, the larvae produced in the treatment and the survivability rate were higher, creating better production efficiency. Therefore, it can be recommended that diets containing 150mg/k astaxanthin be used in warm water fish farming.

In recent years, Aquaculture has an important role to play in The production of animal proteins, employment, and poverty reduction, especially in rural areas. Water supply as a limiting factor in developing countries. Therefore, Multipurpose use of water resources, including, Water use at integrated aquaculture-agriculture farms is a Strategies for Sustainable Development in the world. The aims of this study were to evaluate the optimal utilization of the water reservoir for the development of Rural Aquaculture at Khaneghah Village in Zanjan province. The methodology of research used in this study basically includes a literature survey, Hydrochemical sampled and analyses by standard methods and verification by statistical techniques. Water quality characteristics (physical, chemical) were studied in a water reservoir with approximately 3 hectares. The results showed that the Physical and chemical parameters of the water reservoir were appropriate for the cold and warm water aquaculture. The temperature and climate were the limiting factors for aquaculture activity in the region. Therefore, the water reservoir is more suitable for warm water aquaculture (for First Half of the year). Because the aquaculture production time is short in this area, also its climate is semi-arid. To weight of the carp (up to fingerling) recommended for the water reservoir because it has the lowest cost and can be impacted in Improving Livelihood of Farmers.

The present study has done as a case study in order to assess of effective factors on prosperity and development of rainbow trout farming. The gathering tool of this survey has been questionnaire that has been filled with the visit of rainbow trout farmers in Fars province. Results showed that farms' production was 129. 4 tons that could lead to earning 571 million Toman annually (on average). In terms of aquaculture activities, about 90% of farms have been rearing from fingerling to market fishes. Statistics analysis indicated that some biological factors including water quality, the climate of the region, health management, as well as, some economic factors including the reasonable price of products and insurance coverage, with the average of ranking 27. 65, are the most important of effective indices on prosperity and development of rainbow trout rearing. In addition, among the most significant obstacles to development in this industry, high risk of production (10. 98), construction and repair tax (10. 88), the cost of buying fish food (10. 63), high interest rate of bank loan (10. 3) and the expense of energy tariffs (10. 05) are remarkable. Regarding macro policies usually were applied jointly cross the country, results of identifying and ranking of decisive factors on the prosperity of rainbow trout rearing industry in Fars province could be helpful in the development of this industry around all regions of the country.

The present study was conducted to evaluate the effects of different dosage of the astaxanthin on the pigmentation of the fish fillet and growth parameters and survival in rainbow trout (Oncorhynchus mykiss). Three treatments and the control in three replications have been performed in a completely randomized design plan with 40 fish (100 gr. ) for every rearing tank. The fish of rearing tanks were fed during 8 weeks based on 2% of the biomass by the fish feeds treatments containing 30, 60 and 90 mg/kg astaxantin and one control feed without any astxanthin addition. At the end of experimental period, four fish of every rearing tank were randomly selected to assess the degree of the fillet pigmentation based on L. A. B colorimetric system measuring. No significant improvements of FCR or survival rate were observed between the treatment groups (P>0. 05). Results showed the pigmentation in the treatments of 60 and 90 (the red (*a) parameter) has a significantly different value compared to the control and the other treatment (P<0. 05). Results suggest that the 60 mg/kg astaxanthin was the best and economical concentration to impart the desirable flesh coloration.

In this study, the effect of dietary safflower extract supplementation was investigated on common carp survival and physiological response to salinity stress. To this, the fingerling fish with average weight of 9. 51 ± 0/13 g were fed with diets containing 0, 0. 5, 1. 5 and 3 % safflower extract for 70 days. After this period, some fish were randomly exposed to water salinity of 20 g/l and their mortality was recorded for 10 h. Also, the remaining fish were exposed to water salinity of 14 g/l and their serum biochemical parameters were monitored for 72 h. Results showed that safflower extract had no significant effect on fish growth. After exposure to 20 g/l salinity, mortality in the control fish reached 100 %, but mortality of 0. 5-3% safflower extract groups was 35-50%. After exposure to 14 g/l salinity, serum cortisol and glucose increased and the increment was higher in the control treatment. Also, salinity exposure increased serum sodium and chloride in all of studied groups but there was no significant difference among the treatments. After salinity challenge, serum chloride increased in the control treatment, but in chloride levels of safflower extract no change were recorded. Overall, the results of this study showed that addition of 0. 5-3 % safflower extract to common carp diet increased resistance to salinity challenge and mitigated stress.

This study was conducted in 2015 to identifying problem and limitations of development of carp farming in Rasht. The method of descriptive research was survey research. The statistical population of fish farmers was 1022 around the Rasht and Sangar basin. The samples were determined by using of Bartlett minimum sample size table (n=175) which were conducted with random sampling. The comments of fisheries scientist were gathered by questionnaire forms. For looking for research tool's reliability, 20 questionnaires were completed out of the samples, and the Cronbach's alpha coefficient were obtained (0. 86). The problems were categorized by for section of economic, social, management and extension-education. The most important of economic problems of warm water fish farming were high bank profits, the high cost of ingredient for aquaculture (food, fertilizer, fingerling, fuel, energy, high water charges, etc. ) which ranked first to third, respectively. The low consumption per capita of farmed fish and poor operation of warm water fish farming union were the most important social problems. The lack of farmed fish expert, lack of communication between research centers and fish farms and low rate of production per unit area were the most important management and policy issue. The insufficient training courses, unavailability of the internet and scientific journal for fish farmers and low education levels of fish farmers were the most important technical problems of education and promoting. In this study revision protectionist policy, removing barriers of production, practical training course to improve the technical skills of fish farmers, low-interest loans, to solve problems related to the high cost of factors, promoting of fish consumption and to create necessary infrastructures for processing and storage of fish were proposed.

The purpose of this research, Determination of hematological and biochemical parameters in two species of Acipenseridae, Acipenser stellatus and Acipenser nudiventris In three Age of groups, Fry’ s (2-7 months), Juveniles (1-2 years) and Spanners (7 years). The research at the Institute for International Research sturgeon of the Caspian Sea, in a period of six months (spring and summer) was conducted in 2013. For this reason, 30 numbers of Acipenser Stellatus and 30 numbers of Acipenser nudeventris were used (in each group there were 10 fry’ s, 10 Juveniles, 5 females and 5 males fish). After caudal vein blood vessels, hematological parameters (RBC, WBC, MCV, MCH, MCHC, Hb, PCV, Lym, Mono, Neut, Eos) and biochemical (Serum osmolality, albumin, total protein, glucose, cholesterol, Triglyceride, calcium and magnesium) Determined and studied. The results showed that, RBC, WBC, MCH, MCHC, Hb, Mono, Neut, Eos and total protein, glucose, cholesterol, Triglyceride, calcium and magnesium ions in both sturgeon species (A. nudiventris and A. stellatus) during the 3 groups age difference was statistically significant (p<0/05). But, PCV, Lym, MCV and osmolarity serum, Albumin were only statistically significant difference in the species A. stellatus (p<0/05). Seem to be gender parameters of RBC Mono, and Albumin only in the species A. stellatus and WBC only in the species A. nudiventris has been significant (p<0. 05). A significant statistical difference was estimated in 95% of all data. By investigating the present results, it can be stated that age and species factors in the change of blood parameters are so effective (p<0/05), but gender didn’ t show any effect on the biochemical and hematological parameters. (p>0/05).

The aim of this study was to assess the impact of trout farm effluent on some physicochemical and characteristics biotic indices in Daryaser River (Mazandaran Province). Sampling of water and macrobentic fauna were done in 5 stations (control, in before influent of farm; and other stations include; in 35, 125, 400 and 750 m after effluent were selected in two weekly in summer, 2011. Results showed that farm effluent was not significant difference in many physicochemical parameters (P>0. 05) except nitrate and phosphate parameters in before and after farm effluent. An assessment of biotic indices indicates the health of the Daryasar River. It seems, for low production capacity of the farm and its suitability management, the drainage into Daryasar River has little adverse effects on water health and chemical quantities are in the scope of national standards for effluent discharge in surface water.