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The effect of four light intensities (0, 100, 2000 and 5000 lux) on some reproductive charachteristicsof Artemiaurmianabroodstocks was investigated. 30 male and female individuals were reared in 3 liter containers until the death of all females over the consecutive weeks. Results showed significant differences in terms of average weekly offspring productions among the treatments. The broodstocks cultured in 5000 lux had an increasing trend in offspring production from the first to the fifth week, but a decreasing trend from the sixth to the tenth week. A relatively similar situation was observed in the 2000 lux treatment. The broodstocks cultured in 0 and 100 lux intensities had reduction fluctuations in offspring production from the first to the sixth and seventh weeks, respectively. The highest percentages of egg-sac females were observed in the early and mid-raising weeks, showing the maximum in the mid-week (until the fifth week) in all treatments. In most weeks, a considerable increase was detected in the encysted embryos production in the broodstocks reared in 0 and 100 lux intensities as compared with 2000 and 5000 lux intensities. The survival percentage of broodstocks at the end of the fifth week was 95, 86, 23 and 30 % (in order from high to low levels of light intensities).Considering the increased production of offspring and higher survival rate in the broodstocks as well as the increase in egg-sacsfemales (during the first five weeks), it is recommended that the light intensity of 5000 lux is useful for the mass culture of A. urmianain hatchery reared broodstock.

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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.

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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.