جستجوی مقالات مرتبط با کلیدواژه « artemia urmiana » در نشریات گروه « زیست شناسی »

The aim of this research is the study of the freezing effects at -20°C after hydration and dehydration on the hatching efficiency, survival percentage and growth of Artemia urmiana cysts. Experiments were carried out in four treatments. In the first treatment, hatching was done after one hydration and dehydration cycle with the standard method. In the second treatment, hatching was done after one hydration and dehydration cycle and then one week freezing at -20°C temperature. In third treatment, hatching was done after one hydration and dehydration cycle and then one month freezing at -20°C temperature. Standard hatching was done without any other treatment in the control group (fourth treatment). Results indicated the cyst hatching percentage increased by increasing freezing time (one-month freezing), even though hatching percentage was higher in control group. The most survival percentage was observed in the 11th day of third treatment. The highest growth was in 15 to the 25th day of third treatment (P

Chitin and chitosan are two very important biopolymer products that have so many usages in the high cost industries. Chitin Converts into chitosan via de-acetylation of chitin. It occurs by alkaline melting method in the absence of oxygen. Chemical structure change, severe environmental pollution and De-polymerization are of the major problems in producing high quality chitosan. In this study for conversion of chitin into chitosan fungus Aspergillus niger strains (ATHUM-10864), the generator of de-acetylases enzymes were used instead of chemicals. Chitosan quality was determined via elemental analysis infrared spectroscopy, X-ray tomography, molecular weight determination and estimation of crystallinity percent, color and molecular structure.The results showed 80±5% efficiency in the conversion of chitin into chitosan or de-acetylation degree of chitin. The gained chitosan contained of 44.4 % carbon, 8.9 % nitrogen, 2.7 % hydrogen and 39.5 % oxygen. The physical characteristics were as 94.5% Crystallinity and pale brown color. The chemical structure of per unit of chitosan was obtained as C6H12NO4. The results showed that replacing biological methods instead of chemicals was possible to access well quality products. It also eliminates the use of chemical materials such as concentrate sodium hydroxide that is damaging the environment.

Increasing the application of copper oxide nanoparticles (NPs) in medicine (bactericidal agent) and other industries have raised serious concerns about ecotoxicology and ecophysiology effects on the aquatic animals. In this study¡ the effects of copper oxide NPs enriched yeast on the growth¡ survival; digestive enzymes activity and lipid metabolism in Artemia urmiana (AU) and Artemia franciscana (AF) were investigated. The experiment was designed in two treatments (non- enriched yeast as a control and enriched yeast with copper oxide NPs) and each with four replicates for both Artemia species. At the end of experiment¡ the results indicated that copper oxide NPs did not affect on the Artemia species growth rate but significantly increased both Artemia species survival. Also the results showed¡ copper oxide NPs did not affect on AU digestive enzymes activity¡ but significantly increased AF digestive enzymes activity. The effect of NPs on the body lipid content was investigated in Artemia species and the results revealed that copper oxide NPs significantly decrease AU lipid content but did not affect on AF. The results obtained in this experiment¡ suggest that the ecophysiological effects of copper oxide NPs different in Artemia urmiana and Artemia franciscana.

Selco enriching emulsion includes compounds from certain oils with marine and herbal origins. Selco oil produces micro-globules with less than 0.1 micron diameter. In order to generate such stability in original selco chemical emulsifiers have been used up to 3%. In this study, persian gum )Amygdalus scopariaspeech( and salep (Orchis mascula (were used as herbal emulsifiers in synthesis of Artemia enriching for a content of 11% to establish emulsification. The soluble part of persian gum and salep was separated with 30% and 22% content, respectively. Through chemical analysis, the chemical composition of the imported Selco oil was identified. Then the similar ingredients of the commercial brand were combined to produce our synthesized production. In physical computing, the average diameter and distribution of oil phase particles side was obtained as 0.1 micron and the relevant surface tension as 15±5 DIN/cm. Then the synthesyzed enriching oil (treatment 1) with the imported one (treatment 2) were tested for Artemia urmiana enriching with standard conditions. Enriching conducted in 3 repetitions with 0.4 gr/lit of the enriching oils/1 lit of water. Nauplii were introduced as 200000 nauplii/lit. The average of nauplii enriching percentage in treatments 1 and 2 was achieved as 27±2.47 and 23±2.52 percent, respectively. The bioassay results on 500 new feed larvae of trout fish has been shown that treatments 1 and 2 were significantly differed in survival. Therefore, the plant emulsifiers in this study, showed good performances as the chemical and physical properties, in stabilizing the oil emulsion in the aqueous phase.

This study was performed to compare the efficiency of 6 microalgae namely Dunaliella tertiolecta, Tetraselmis suecica, Chlorella sp., (green algae), Nannochloropsis oculata, Spirolina sp.(blue-green algae) Cheatocerus sp. (Diatoma), and Isochrices sp. (Haptophytae) on the growth, survival and reproduction efficacy in Artemia urmiana in laboratory conditions. Artemia cysts were harvested from Urmia Lake and hatched according to the standard method. Live microalgae were cultured using the F/2 Guillard's culture medium. Artemia survival was determined in treatments on days 8, 11, 14, 17 and 20. Length growth of A. urmiana was measured in three-day intervals. To determine reproduction efficiency characteristics such as cysts production, intervals between two successive reproductions, first reproduction time and the date of female Artemia were analyzed. The results indicated a significant difference (p

Nowadays, nanoparticles (NPs) have a great potential application in different industries. Titanium dioxide NPs cause the biggest eco-toxicological and eco-physiological concerns due to the increase of anthropogenic input into the aquatic ecosystems, compared with other NPs. In this study, the impact of yeast enriched with titanium dioxide NPs on the growth, survival, digestive enzyme activity and lipid metabolism in Artemia urmiana (AU) and Artemia franciscana (AF) is investigated. The experiment was designed in two treatments (control and enriched yeast with titanium dioxide NPs) and each with four replicates for both Artemia species. The investigation indicated that titanium dioxide nanoparticles did not affect the Artemia species growth but increased AF survival significantly. However, No significant difference was observed in AU survival. Also, the results showed that NPs decreased AU digestive enzyme activity significantly and the reverse pattern was observed for AF. The impact of NPs on the body lipid content was investigated in Artemia species and the results revealed that using this NPs decrease this parameter in AU but did not affect on AF lipid body content. The results obtained in this experiment suggest that the eco-physiological effects of titanium dioxide NPs differ in Artemia urmiana and Artemia franciscana.

Artemia, as live food, is of vital importance in aquaculture. In this study, we have studied the helium-neon (He-Ne) laser beam with 10 mw on the hatching and life span of Artemia cysts. He-Ne laser irradiation was performed with a 10 mw power at 3, 4 and 5 h irradiation periods. Cysts were hatched by standard method. Hatching percentage after 4 h of irradiation was more than other treatments after 18 and 24 h of hatching. We compared the lifespan of this treatment which showed that this treatment was more than the control in females (12 days) and males (10 days; P

This research was performed to introduce a standard protocol for enrichment of Artemia urmian with Canola oil. Artemia urmiana nauplii were enriched at three densities (50000، 100000 and 200000 nauplii L-1) and three concentrations of Canola oil (0. 1، 0. 2 and 0. 3 g L-1). Their effects were evaluated on survival، total length and profile of fatty acids at 6، 9، 12، 15 and 18 hours after the onset of enrichment. Cysts of A. urmiana were hatched according to the standard method. A. urmiana nauplii were stocked at above densities in 7 L cylindrical containers. Canola oil emulsion was added at concentrations of 0. 1، 0. 2 and 0. 3 g L-1 at the beginning and 12 hours after the onset of enrichment. The results of analysis showed that enrichment of A. urmiana with 0. 3 g L-1 Canola oil at 100000 nauplii L-1 for 18 hours was considered as the best treatment. Artemia nauplii enriched in this treatment had significantly higher levels of (n-3) PUFA and survival and minimum total length comparing to other treatments. The treatment had significantly higher levels of (n-6) PUFA than all treatments except treatment with a density of 50،000 nauplii L-1 with 0. 1 g L-1 Canola oil for 18 hours.

Artemia nauplii, despite their marine origin, have a good potential for application in the freshwater ornamental fish culture. In this study, Artemia urmiana and A. franciscana were used for feeding Guppy (Poecilia reticulata Peters) larvae. Newly hatched nauplii at three different densities of 3, 6, and 12 ind./ml as live feed were compared for measuring larval ingestion rate. Results showed that type and density of Artemia nauplii had significant effects on ingestion rate (P<0.05). The average ingestion rate in larvae which were maintained at 12 hours starvation (first set of experiment) were 36, 244, and 664 ind./larvae/day for A. urmiana, 160, 480, and 880 ind./larvae/day for A. fransiscana at densities of 3, 6, and 12 ind./ml, respectively. The average ingestion rate of guppy larvae with 24, 48 and 72 hours feeding preconditions (2nd, 3rd and 4th set of experiment) significantly (P<0.05) decreased. After starvation, the ingestion rate of guppy larvae fed A. urmiana ranged between 22-54, 86-102, and 148-188 ind./larvae/day, for A. franciscana 66-100, 100-260, and 200-224 ind./larvae/day at 3, 6, and 12 ind./ml, respectively. The use of suitable densities of 6 and 12 ind./ml from Artemia nauplii could increase efficiency of utilization and also improve guppy larvae production.

Considering the economic importance of Artemia in sturgeons fed and use as different business foods with the aim of breeding of this aquatic organism as well as definition the role of appropriate nutrition of this animal increase its nutritional value, how to extract beer yeast as lettuce and two types of common foods in the rearing business, the rate of growth was studied. To achieve this goal, the amount of 0.5 grams of Artemia eggs were decapsulate urmiana Artemia which is native species of Iran were cultivated at zok Incubation with one liter volume. Salt levels and temperature during rearing, 35 grams per liter and 28°C temperature were constant. The measurement and investigate breeding stages with stage fed directly from the environment using brewer's yeast and, lettuce extracts were fed. Results of measuring the frequency and distribution of samples in studied stages, using SAS software, showed a significant difference in feeding period between these two nutrients. There wasnt any significant difference in feeding period between two used nutrients. The growth variations in both studied groups were similar.