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The nutritional value and special properties of Artemia have led to its use as a food and biological model in aquaculture. L-Carnitine supplementation stimulates the oxidation of fatty acids, increases nitrogen retention and resistance to environmental stress, and L-Arginine nutritional supplementation is effective in protein synthesis, nitric acid and growth hormone growth and survival. In this study, the effect of Nanochloropsis oculata micro algae enriched with L-carnitine and L-arginine supplements on growth, environmental stress, absolute fecundity and saturated fatty acid profile in Artemia feransiscana was investigated. L-carnitine and L-arginine were applied separately at concentrations of 0, 1, 10, 100 and 1000 mg/l. Artemia cysts under special hatching conditions and Napolius were fed with N. oculata microalgae with two states, enriched conditions and without enrichment (control treatment) separately in 30 days. The results were compared and it was shown that the highest saturated fatty acid (SFA) with nutritional treatment L-carnitine 10 mg/l and the lowest was in the control treatment. The highest mortality percentage of ammonia shock was related to rich treatment with 1 and 100 mg/l L-carnitine which showed a significant difference with the control treatment (p<0.05) and the lowest was related to 1 mg/l L-arginine treatment and control treatment. In hypoxia shock, the highest mortality percentage was observed in the diet with L-carnitine 1 and L-arginine 1 and 100 mg/l and the lowest in the diet with L-carnitine 10 mg/l, all of which showed a significant difference with the control treatment (p<0.05). In  adult Artemia breeders,  the lowest quality indicators  were related to L-carnitine treatment at all doses except 1000 mg/l and the highest were related to L-arginine treatment except 100 mg/l plus 1000 mg/l. L- carnitine that showed a significant difference with the control treatment (p<0.05) .The highest amount of absolute fecundity is related to the nutritional treatment rich in L-arginine 1000 mg/l and the lowest is the control treatment, which shows the positive effect of both supplements on increasing the absolute fecundity. Overall, the results showed that the use of the mentioned nutritional supplements with N. oculata microalgae in A. franciscana nutrition in specific doses can be effective in increasing production and quality in the aquaculture industry. Therefore, according to the environmental stress conditions, improving the fecundity performance and achieving a higher quality index, the optimal doses of each supplement can be used.

Effects of dietary supplementation of red macroalgae Gracilaria pygmea on the growth performance, hematology and serum biochemistry parameters of Asian Seabass Lates calcarifer with initial fish weight of 28±5.9 g were investigated in a 6-week experiment. The experimental diets were composed of the positive control diet (containing fishmeal), the negative control diet (containing fishmeal-soy protein) and three diets which supplemented with varying leves of red algae (3, 6 and 9%). Results indicated that daily growth rate, feed conversion ratio and final weight of fish not only were not negatively affected by different substitution levels of red algae, but also the final weight of fish fed the diet containing 6% red algae was higher than the other experimental diets. Condition factor of the negative control group and the specific growth rate of the treatment containing 6% red algae were significantly higher than those of the other experimental diets (P0.05). Among the examined serum biochemistry parameters of Asian Seabass, only glucose was not significantly affected by various dietary treatments (P>0.05). The cholesterol levels of the negative control group and fish fed the diet containing 9% red algae were similar with each other and were significantly higher than the other treatments (P