نشریه بهره برداری و پرورش آبزیان
سال سوم شماره 3 (پاییز 1393)

The objective of this study was to evaluate the effect of five dosage of vitamin C (0, 50, 250, 750 and 1500 mg vitamin C per kg diet) on fatty acid composition of Caspian brown trout fry (Salmo trutta caspius). Fish (initial average body weight of 0.1 ± 0.02 g) were fed by formulated diets for 6 weeks in triplicate. The findings of growth parameters and survival showed significant difference among groups (P< 0.05). The lowest amount of SGR, BWG and survival was observed in control group while the group of 750 mg/kg had the highest amount of SGR, BWG and survival than those from others.The results showed that fish fed 750 mg/kg diet had a higher PUFA, HUFA, n-3 and n-6 fatty acids than those from other groups without significantdifference (p > 0.05). Control treatment had a lower amount of PUFA, HUFA, n-3 and n-6 fatty acids than those from other treatments without significant (p>0.05). The SFA fatty acids had a higher amount in 1500 mg/kg diet than those from others without significant difference (p > 0.05). These results showed that vitamins C could be have an important role in protection of fatty acids against oxidation.

In this study parasite infestation of Cyprinoids farms of Golestan province have been studied. For this purpose 16 farms in 2009 and 15 farms in 2008 have been randomly selected, totally 1860 specimens has been studied for 2 years. According to the result of this study% 93.3 and %56.25 of farms had parasite infestations in 2009 and 2008 respectively. Trichodina sp has maximum parasite infestation prevalence with % 60 and abundance of %16.25 ± 8.96, then Gyrodactylusspp and Dactylogyrusspp infestation with prevalence of % 33.3 and mean abundance % 21 ± 7.33 and % 12.8 ± 5.97 respectively. The prevalence and abundance of Lernea sp was % 6.66 and % 9 respectively and Saprolegniosis estimated as % 13.33 in 2009. In 2008 prevalence and abundance of parasite infestations for Trichodina sp was % 43.7 and %15.85 ± 8.43, Dactylogyrus sp infestation was % 18.7 and %16.33 ± 13.05, Gyroductylus sp infestation was % 18.7 and % 29 ± 7.21, Lernea sp infestation % 6.25 and % 6 respectively. Prevalence of parasite infestation of warm water cultures in this study in 2009 estimated more than 2008, but there was no significant difference for abundance of parasites in infested farms (P ≤0.05).

In this study, the extract of sea cucumber species, Holothuria leucospilota was extracted and its effect studied on the chemical Quality Rainbow trout fillets packed in vacuum. Sea cucumber was extracted using methanol and various concentrations (0, 5/0, 1 and 2%) were prepared. Salmon fillets after soaking in the extracts were vacuum packed, chemical tests every 4 days included total volatile nitrogenous bases (TVB-N), thiobarbitoric acid (TBA) and pH was performed on the samples. The results showed that the samples treated with the extract of sea cucumber TVB-N levels were more than acceptable; this result could be due to the anti-bacterial extracts. TBA levels in all treatments from day 12 to the extent that it exceeds the amount of control samples than in samples treated with the extract. Increased acidity in some days and some days are reduced. However, pH control samples during storage of the samples treated with rosemary extract. The results showed that the separated species of sea cucumber extract has antibacterial properties, but only up to 12 days storage of fat to prevent corruption. The overall results of this research extracts 1% of sea cucumbers propose to keep rainbow trout fillets in the refrigerator.

Nowadays, the management of water resources by planning through appropriate site selection, fish species storage and selection, enforcement and providing various side services has become a profitable, entrepreneurial and fun process. Survey and usage of development of fee-fishing experience in the world wide represent a model in order to a better economical and fun plan offers and environmentally compatible. In addition to paying attention to the environment, its economic aspect will also be considered, as well. Water management is the only one part of management process alongside of human resource management, insurance benefits, selling license and equipments, training, employment, security and peace in the country that requires special attention. Iran In addition of catching over 38000 tons of fish from inland water resources, also has abundant of water resources planning and management for sports fishing This article presents offers to improve the performance of fee-fishing activities by reviewing evidence about the operation of water resources investment and development in Iran.

Heavy metals are toxic elements which have a harmful effect on the natural environment and its habitats. Investigation of the effect of rose mallow extract on physiological potential improvement of common carp is the aim of this study. 150 fish juvenile (50-100 gram) have been considered for a 14 days in four groups including control, pre treatment, metal only and metal+rose mallow extract. For determining biochemical alteration, blood sampling and have done third, seventh and fourteenth days after exposure with combined concentration of cadmium and lead. Results showed that there were not any significant difference about LDH, AST, ALP, cholesterol, total protein and glucose for groups which picked up rose mallow extract in their diet respect to the control. On the other hand, significant difference was determined in rose mallow free diets group after metal exposure. Based of obtained results, it seems that, using rose mallow extract in diet have an acceptable potency in improving fish physiological tolerance respect to the environmental pollutions.

The aim of this study was comparative study of the effects of two prebiotics, fructooligosaccharide (FOS) and yeast based prebiotic (YBP), on intestinal microbiota of beluga (Huso huso) juvenile. The study was done in a complete randomize design include feeding beluga with diet contain either 1 or 2% yeast based prebiotic or fructooligosaccharide as well as a control group (5 treatments in triplicates). Beluga (11.40±0.56 g) were supplied, 35 specimens stocked in each fiberglass tanks and were fed with experimental diets for 6 weeks. At the end of trial total viable bacteria, LAB and their proportion was studied using culture based method. Our results showed that administration of FOS or YBP had no significant effects on total viable bacteria compared to control group (P > 0.05). The highest LAB levels observed in 2% FOS or YBP fed fish which was significantly higher than control (P < 0.05). The proportion of LAB to total viable bacteria was significantly elevated in all prebiotic fed fish (P < 0.05) and the highest proportion observed in 2% FOS fed beluga.

In this study the mixture of commercial and autochthonous Bacillus subtilis and Bacillus licheniformis isolated from gut of Huso huso fingerling were used for enhancement of body composition and feeding parameters of whiteleg shrimp (Litopenaeus vannamei). The experiment was carried out in completely randomized design. Three replicates for each treatments and control group were used. The post larvae in treatments of 1 and 3 were fed by supplemented diets with commercial and autochthonous Bacillus in concentration of 1.5×106 CFU/g respectively. The supplemented diet with blend of commercial and autochthonous Bacillus in concentration of 1.5×106 CFU/g were used in treatment of 2. The post larvae in control were fed on nonsupplemented diet with Bacillus. At the end of the period (60 days) the larvae were sampled and the proximate body compositions of them were determined. The results indicated that the shrimp larvae in treatment 1 had highest weight and survival rate in comparison with control. The maximum of level of carcass crude protein (46.98%) and lowest of crude lipid (2.40%) were obtained in treatment of 1 and had significantly difference with the control (P

The mucus layer on the skin of fish contain a several of antimicrobial compounds that provide a first line of defense against fish pathogens. This study was conducted to evaluate the effects of different levels of prebiotic GroBiotic®-A on antimicrobial activity and some immune parameters of mucus of cultured juvenile beluga (Huso huso). For this purpose, four groups of beluga sturgeon with mean weight of 40.82± 5.8 g were raised for 8 weeks in fiber glass tanks (20 fish to each tank) and feeding with different levels of GroBiotic®-A with concentrations of % 0, % 0.5, %1.0 and % 2.0. At the end of trial, mucus was collected from the surface of the skin and its antibacterial activity against some common pathogenic bacteria was evaluated by disk diffusion and serial dilution methods. Results showed by increasing the concentration of GroBiotic®-A, significant diffirences in inhibition zone diameter, soluble protein content and alkaline phosphatase activity of mucus was observed in compare to control groups(P< 0.05). Similar results was observed in serial dilution method. MIC test showed a minimum concentrations of mucus ranged between 25 to 250 μg/l were able to inhibit the growth of the selected bacterial. Based on the results, using of GroBiotic®-A, especially at the level of 2.0%, in order to increased the antimicrobial activity, soluble protein content and alkaline phosphatase activity of mucus of farmed beluga was recommended.

During this study, the effect of morning liming on water quality of cultured carps in Dikjeh area of Gonbad was investigated. Nine ponds (3 hectars) were chosen and divided to 3 treatments including; (1-liming 750 mg/l, 2-liming 1250 mg/l and 3-liming 1750 mg/l). Limning was done at 7 and 8 oclock in the morning and weekly. In definite intervals, sampling from water was done and physicochemical conditions of water were investigated. According to our results, liming had significant effect on hardness (P